1638566252 has 12 divisors (see below), whose sum is σ = 2867786376. Its totient is φ = 819198720.

The previous prime is 1638566243. The next prime is 1638566257. The reversal of 1638566252 is 2526658361.

It is not an unprimeable number, because it can be changed into a prime (1638566257) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46988 + ... + 74060.

It is an arithmetic number, because the mean of its divisors is an integer number (238982198).

Almost surely, 2^1638566252 is an apocalyptic number.

It is an amenable number.

1638566252 is a deficient number, since it is larger than the sum of its proper divisors (1229220124).

1638566252 is a wasteful number, since it uses less digits than its factorization.

1638566252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42208 (or 42206 counting only the distinct ones).

The product of its digits is 518400, while the sum is 44.

The square root of 1638566252 is about 40479.2076503481. The cubic root of 1638566252 is about 1178.9299530603.

The spelling of 1638566252 in words is "one billion, six hundred thirty-eight million, five hundred sixty-six thousand, two hundred fifty-two".