1991479876 has 27 divisors (see below), whose sum is σ = 3560544183. Its totient is φ = 974631840.

The previous prime is 1991479859. The next prime is 1991479891. The reversal of 1991479876 is 6789741991.

The square root of 1991479876 is 44626.

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

It can be written as a sum of positive squares in 4 ways, for example, as 437228100 + 1554251776 = 20910^2 + 39424^2 .

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, 4730146 + ... + 4730566.

Almost surely, 2^1991479876 is an apocalyptic number.

1991479876 is the 44626-th square number.

It is an amenable number.

1991479876 is a deficient number, since it is larger than the sum of its proper divisors (1569064307).

1991479876 is an frugal number, since it uses more digits than its factorization.

1991479876 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 952 (or 476 counting only the distinct ones).

The product of its digits is 6858432, while the sum is 61.

The cubic root of 1991479876 is about 1258.1293893570.

The spelling of 1991479876 in words is "one billion, nine hundred ninety-one million, four hundred seventy-nine thousand, eight hundred seventy-six".