400635120 has 40 divisors (see below), whose sum is σ = 1241969616. Its totient is φ = 106835968.

The previous prime is 400635101. The next prime is 400635127. The reversal of 400635120 is 21536004.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400635127) 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, 834417 + ... + 834896.

Almost surely, 2^400635120 is an apocalyptic number.

400635120 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400635120 is an abundant number, since it is smaller than the sum of its proper divisors (841334496).

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

400635120 is a wasteful number, since it uses less digits than its factorization.

400635120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1669329 (or 1669323 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 400635120 is about 20015.8717022267. The cubic root of 400635120 is about 737.1960605276.

The spelling of 400635120 in words is "four hundred million, six hundred thirty-five thousand, one hundred twenty".