1978931495025 has 135 divisors (see below), whose sum is σ = 3758065012251. Its totient is φ = 1029467244960.

The previous prime is 1978931495011. The next prime is 1978931495033. The reversal of 1978931495025 is 5205941398791.

The square root of 1978931495025 is 1406745.

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

1978931495025 is a `hidden beast` number, since 1 + 9 + 7 + 89 + 3 + 1 + 49 + 502 + 5 = 666.

It can be written as a sum of positive squares in only one way, i.e., 712415338209 + 1266516156816 = 844047^2 + 1125396^2 .

It is a tau number, because it is divible by the number of its divisors (135).

It is not a de Polignac number, because 1978931495025 - 2³³ = 1970341560433 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 2722051212 + ... + 2722051938.

Almost surely, 2^{1978931495025} is an apocalyptic number.

1978931495025 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1978931495025 is the 1406745-th square number.

1978931495025 is the 703373-rd centered octagonal number.

It is an amenable number.

1978931495025 is a deficient number, since it is larger than the sum of its proper divisors (1779133517226).

1978931495025 is an frugal number, since it uses more digits than its factorization.

1978931495025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1562 (or 778 counting only the distinct ones).

The product of its (nonzero) digits is 24494400, while the sum is 63.

The spelling of 1978931495025 in words is "one trillion, nine hundred seventy-eight billion, nine hundred thirty-one million, four hundred ninety-five thousand, twenty-five".