891787479025 has 9 divisors (see below), whose sum is σ = 1105822328961. Its totient is φ = 713426205840.

The previous prime is 891787479013. The next prime is 891787479083. The reversal of 891787479025 is 520974787198.

The square root of 891787479025 is 944345.

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 106323601329 + 785463877696 = 326073^2 + 886264^2 .

It is not a de Polignac number, because 891787479025 - 2²³ = 891779090417 is a prime.

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, 4627291 + ... + 4816159.

Almost surely, 2^891787479025 is an apocalyptic number.

891787479025 is the 944345-th square number.

891787479025 is the 472173-rd centered octagonal number.

It is an amenable number.

891787479025 is a deficient number, since it is larger than the sum of its proper divisors (214034849936).

891787479025 is an frugal number, since it uses more digits than its factorization.

891787479025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377748 (or 188874 counting only the distinct ones).

The product of its (nonzero) digits is 71124480, while the sum is 67.

The spelling of 891787479025 in words is "eight hundred ninety-one billion, seven hundred eighty-seven million, four hundred seventy-nine thousand, twenty-five".