1638774472 has 64 divisors (see below), whose sum is σ = 3402547200. Its totient is φ = 736464960.

The previous prime is 1638774463. The next prime is 1638774479. The reversal of 1638774472 is 2744778361.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (1638774479) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 442147 + ... + 445837.

It is an arithmetic number, because the mean of its divisors is an integer number (53164800).

Almost surely, 2^1638774472 is an apocalyptic number.

It is an amenable number.

1638774472 is an abundant number, since it is smaller than the sum of its proper divisors (1763772728).

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

1638774472 is a wasteful number, since it uses less digits than its factorization.

1638774472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3866 (or 3862 counting only the distinct ones).

The product of its digits is 1580544, while the sum is 49.

The square root of 1638774472 is about 40481.7795063409. The cubic root of 1638774472 is about 1178.9798882597.

The spelling of 1638774472 in words is "one billion, six hundred thirty-eight million, seven hundred seventy-four thousand, four hundred seventy-two".