400021009252 has 48 divisors (see below), whose sum is σ = 709902325440. Its totient is φ = 197210096000.

The previous prime is 400021009249. The next prime is 400021009277. The reversal of 400021009252 is 252900120004.

It is a super-4 number, since 4×400021009252⁴ (a number of 48 digits) contains 4444 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 109323399 + ... + 109327057.

It is an arithmetic number, because the mean of its divisors is an integer number (14789631780).

Almost surely, 2^400021009252 is an apocalyptic number.

It is an amenable number.

400021009252 is a deficient number, since it is larger than the sum of its proper divisors (309881316188).

400021009252 is a wasteful number, since it uses less digits than its factorization.

400021009252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4812 (or 4810 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 25.

Adding to 400021009252 its reverse (252900120004), we get a palindrome (652921129256).

The spelling of 400021009252 in words is "four hundred billion, twenty-one million, nine thousand, two hundred fifty-two".