400694400 has 144 divisors (see below), whose sum is σ = 1429872210. Its totient is φ = 106844160.

The previous prime is 400694389. The next prime is 400694407. The reversal of 400694400 is 4496004.

It can be written as a sum of positive squares in 3 ways, for example, as 321413184 + 79281216 = 17928^2 + 8904^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (400694407) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 21844 + ... + 35756.

Almost surely, 2^400694400 is an apocalyptic number.

400694400 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 400694400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (714936105).

400694400 is an abundant number, since it is smaller than the sum of its proper divisors (1029177810).

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

400694400 is a wasteful number, since it uses less digits than its factorization.

400694400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13943 (or 13923 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 400694400 is about 20017.3524722926. The cubic root of 400694400 is about 737.2324184878.

The spelling of 400694400 in words is "four hundred million, six hundred ninety-four thousand, four hundred".