1988173087 has 4 divisors (see below), whose sum is σ = 1990668456. Its totient is φ = 1985677720.

The previous prime is 1988173081. The next prime is 1988173141. The reversal of 1988173087 is 7803718891.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1988173087 - 2²³ = 1979784479 is a prime.

It is a super-2 number, since 2×1988173087² = 7905664447742219138, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1988173081) 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, 1246489 + ... + 1248082.

It is an arithmetic number, because the mean of its divisors is an integer number (497667114).

Almost surely, 2^1988173087 is an apocalyptic number.

1988173087 is a deficient number, since it is larger than the sum of its proper divisors (2495369).

1988173087 is an equidigital number, since it uses as much as digits as its factorization.

1988173087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2495368.

The product of its (nonzero) digits is 677376, while the sum is 52.

The square root of 1988173087 is about 44588.9345802297. The cubic root of 1988173087 is about 1257.4326422927.

The spelling of 1988173087 in words is "one billion, nine hundred eighty-eight million, one hundred seventy-three thousand, eighty-seven".