18987737616 has 45 divisors (see below), whose sum is σ = 53143921519. Its totient is φ = 6328694688.

The previous prime is 18987737581. The next prime is 18987737621. The reversal of 18987737616 is 61673778981.

The square root of 18987737616 is 137796.

It is a perfect power (a square), and thus also a powerful number.

18987737616 is a `hidden beast` number, since 1 + 8 + 9 + 8 + 7 + 7 + 3 + 7 + 616 = 666.

It is a super-2 number, since 2×18987737616² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1647811 + ... + 1659293.

Almost surely, 2^18987737616 is an apocalyptic number.

18987737616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

18987737616 is the 137796-th square number.

It is an amenable number.

18987737616 is an abundant number, since it is smaller than the sum of its proper divisors (34156183903).

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

18987737616 is an frugal number, since it uses more digits than its factorization.

18987737616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22980 (or 11488 counting only the distinct ones).

The product of its digits is 21337344, while the sum is 63.

The spelling of 18987737616 in words is "eighteen billion, nine hundred eighty-seven million, seven hundred thirty-seven thousand, six hundred sixteen".