402351021 has 6 divisors (see below), whose sum is σ = 581173710. Its totient is φ = 268234008.

The previous prime is 402351007. The next prime is 402351041. The reversal of 402351021 is 120153204.

It can be written as a sum of positive squares in only one way, i.e., 311910921 + 90440100 = 17661^2 + 9510^2 .

It is not a de Polignac number, because 402351021 - 2⁵ = 402350989 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 402350985 and 402351003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402351041) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22352826 + ... + 22352843.

It is an arithmetic number, because the mean of its divisors is an integer number (96862285).

Almost surely, 2^402351021 is an apocalyptic number.

It is an amenable number.

402351021 is a deficient number, since it is larger than the sum of its proper divisors (178822689).

402351021 is a wasteful number, since it uses less digits than its factorization.

402351021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44705675 (or 44705672 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 402351021 is about 20058.6894138176. The cubic root of 402351021 is about 738.2470200040.

The spelling of 402351021 in words is "four hundred two million, three hundred fifty-one thousand, twenty-one".