400552128 has 70 divisors (see below), whose sum is σ = 1187377356. Its totient is φ = 133515648.

The previous prime is 400552127. The next prime is 400552151. The reversal of 400552128 is 821255004.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (400552127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 33450 + ... + 43817.

Almost surely, 2^400552128 is an apocalyptic number.

400552128 is a gapful number since it is divisible by the number (48) formed by its first and last digit.

It is an amenable number.

400552128 is an abundant number, since it is smaller than the sum of its proper divisors (786825228).

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

400552128 is an equidigital number, since it uses as much as digits as its factorization.

400552128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77291 (or 77272 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

The square root of 400552128 is about 20013.7984400763. The cubic root of 400552128 is about 737.1451533576.

The spelling of 400552128 in words is "four hundred million, five hundred fifty-two thousand, one hundred twenty-eight".