402350444721 has 81 divisors (see below), whose sum is σ = 621828964939. Its totient is φ = 260321234400.

The previous prime is 402350444711. The next prime is 402350444761. The reversal of 402350444721 is 127444053204.

The square root of 402350444721 is 634311.

It is a perfect power (a square), and thus also a powerful number.

402350444721 is a `hidden beast` number, since 40 + 2 + 3 + 504 + 44 + 72 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 19387499121 + 382962945600 = 139239^2 + 618840^2 .

It is a tau number, because it is divible by the number of its divisors (81).

It is not a de Polignac number, because 402350444721 - 2¹⁹ = 402349920433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (402350444701) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 2106546736 + ... + 2106546926.

Almost surely, 2^402350444721 is an apocalyptic number.

402350444721 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

402350444721 is the 634311-st square number.

402350444721 is the 317156-th centered octagonal number.

It is an amenable number.

402350444721 is a deficient number, since it is larger than the sum of its proper divisors (219478520218).

402350444721 is an frugal number, since it uses more digits than its factorization.

402350444721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 488 (or 235 counting only the distinct ones).

The product of its (nonzero) digits is 107520, while the sum is 36.

Multiplying 402350444721 by its sum of digits (36), we get a square (14484616009956 = 3805866²).

Adding to 402350444721 its reverse (127444053204), we get a palindrome (529794497925).

The spelling of 402350444721 in words is "four hundred two billion, three hundred fifty million, four hundred forty-four thousand, seven hundred twenty-one".