18971493240 has 64 divisors (see below), whose sum is σ = 65045122560. Its totient is φ = 4336341120.

The previous prime is 18971493223. The next prime is 18971493253. The reversal of 18971493240 is 4239417981.

It is a self number, because there is not a number n which added to its sum of digits gives 18971493240.

It is a congruent number.

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, 11291716 + ... + 11293395.

It is an arithmetic number, because the mean of its divisors is an integer number (1016330040).

Almost surely, 2^18971493240 is an apocalyptic number.

18971493240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18971493240 is an abundant number, since it is smaller than the sum of its proper divisors (46073629320).

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

18971493240 is a wasteful number, since it uses less digits than its factorization.

18971493240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22585132 (or 22585128 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 48.

The spelling of 18971493240 in words is "eighteen billion, nine hundred seventy-one million, four hundred ninety-three thousand, two hundred forty".