400389072 has 40 divisors (see below), whose sum is σ = 1036749120. Its totient is φ = 133152000.

The previous prime is 400389053. The next prime is 400389079. The reversal of 400389072 is 270983004.

It is a super-2 number, since 2×400389072² = 320622817954042368, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400389079) 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, 11572 + ... + 30572.

It is an arithmetic number, because the mean of its divisors is an integer number (25918728).

Almost surely, 2^400389072 is an apocalyptic number.

It is an amenable number.

400389072 is an abundant number, since it is smaller than the sum of its proper divisors (636360048).

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

400389072 is a wasteful number, since it uses less digits than its factorization.

400389072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19451 (or 19445 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 400389072 is about 20009.7244358837. The cubic root of 400389072 is about 737.0451145652.

The spelling of 400389072 in words is "four hundred million, three hundred eighty-nine thousand, seventy-two".