1918668840 has 64 divisors (see below), whose sum is σ = 6279284160. Its totient is φ = 465131520.

The previous prime is 1918668839. The next prime is 1918668863. The reversal of 1918668840 is 488668191.

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, 725449 + ... + 728088.

It is an arithmetic number, because the mean of its divisors is an integer number (98113815).

Almost surely, 2^1918668840 is an apocalyptic number.

1918668840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1918668840 is an abundant number, since it is smaller than the sum of its proper divisors (4360615320).

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

1918668840 is a wasteful number, since it uses less digits than its factorization.

1918668840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1453562 (or 1453558 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 51.

The square root of 1918668840 is about 43802.6122508692. The cubic root of 1918668840 is about 1242.6056982226.

The spelling of 1918668840 in words is "one billion, nine hundred eighteen million, six hundred sixty-eight thousand, eight hundred forty".