401639264 has 48 divisors (see below), whose sum is σ = 871394832. Its totient is φ = 181052928.

The previous prime is 401639257. The next prime is 401639269. The reversal of 401639264 is 462936104.

It is a super-2 number, since 2×401639264² = 322628196772923392, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401639269) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6662 + ... + 29114.

It is an arithmetic number, because the mean of its divisors is an integer number (18154059).

Almost surely, 2^401639264 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 401639264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (435697416).

401639264 is an abundant number, since it is smaller than the sum of its proper divisors (469755568).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

401639264 is a wasteful number, since it uses less digits than its factorization.

401639264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22519 (or 22511 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 35.

The square root of 401639264 is about 20040.9396985271. The cubic root of 401639264 is about 737.8114445963.

The spelling of 401639264 in words is "four hundred one million, six hundred thirty-nine thousand, two hundred sixty-four".