401257635601 has 3 divisors (see below), whose sum is σ = 401258269051. Its totient is φ = 401257002152.

The previous prime is 401257635509. The next prime is 401257635617. The reversal of 401257635601 is 106536752104.

The square root of 401257635601 is 633449.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 213213986001 + 188043649600 = 461751^2 + 433640^2 .

It is not a de Polignac number, because 401257635601 - 2³³ = 392667701009 is a prime.

It is a super-2 number, since 2×401257635601² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (401257635301) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 316725 + ... + 950173.

Almost surely, 2^401257635601 is an apocalyptic number.

401257635601 is the 633449-th square number.

401257635601 is the 316725-th centered octagonal number.

It is an amenable number.

401257635601 is a deficient number, since it is larger than the sum of its proper divisors (633450).

401257635601 is an frugal number, since it uses more digits than its factorization.

401257635601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1266898 (or 633449 counting only the distinct ones).

The product of its (nonzero) digits is 151200, while the sum is 40.

The spelling of 401257635601 in words is "four hundred one billion, two hundred fifty-seven million, six hundred thirty-five thousand, six hundred one".