400651920 has 200 divisors, whose sum is σ = 1473782904. Its totient is φ = 100528128.

The previous prime is 400651919. The next prime is 400651921. The reversal of 400651920 is 29156004.

400651920 is a `hidden beast` number, since 4 + 0 + 0 + 651 + 9 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (400651919) and next prime (400651921).

It can be written as a sum of positive squares in 4 ways, for example, as 10036224 + 390615696 = 3168^2 + 19764^2 .

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 (400651921) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 108342 + ... + 111978.

Almost surely, 2^400651920 is an apocalyptic number.

400651920 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400651920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (736891452).

400651920 is an abundant number, since it is smaller than the sum of its proper divisors (1073130984).

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

400651920 is a wasteful number, since it uses less digits than its factorization.

400651920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3679 (or 3664 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 400651920 is about 20016.2913647858. The cubic root of 400651920 is about 737.2063647672.

The spelling of 400651920 in words is "four hundred million, six hundred fifty-one thousand, nine hundred twenty".