1917131980 has 12 divisors (see below), whose sum is σ = 4025977200. Its totient is φ = 766852784.

The previous prime is 1917131969. The next prime is 1917131981. The reversal of 1917131980 is 891317191.

It is not an unprimeable number, because it can be changed into a prime (1917131981) 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, 47928280 + ... + 47928319.

It is an arithmetic number, because the mean of its divisors is an integer number (335498100).

Almost surely, 2^1917131980 is an apocalyptic number.

1917131980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1917131980 is an abundant number, since it is smaller than the sum of its proper divisors (2108845220).

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

1917131980 is a wasteful number, since it uses less digits than its factorization.

1917131980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95856608 (or 95856606 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 40.

The square root of 1917131980 is about 43785.0657188042. The cubic root of 1917131980 is about 1242.2738325256.

The spelling of 1917131980 in words is "one billion, nine hundred seventeen million, one hundred thirty-one thousand, nine hundred eighty".