91827890139969 has 15 divisors (see below), whose sum is σ = 137175125215953. Its totient is φ = 61218535930524.

The previous prime is 91827890139917. The next prime is 91827890140003. The reversal of 91827890139969 is 96993109872819.

The square root of 91827890139969 is 9582687.

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

91827890139969 is a `hidden beast` number, since 9 + 1 + 82 + 7 + 8 + 90 + 1 + 399 + 69 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-91827890139969 is a prime.

It is a super-2 number, since 2×91827890139969² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is not an unprimeable number, because it can be changed into a prime (91827890138969) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 85711812 + ... + 86776554.

Almost surely, 2^{91827890139969} is an apocalyptic number.

91827890139969 is the 9582687-th square number.

91827890139969 is the 4791344-th centered octagonal number.

It is an amenable number.

91827890139969 is a deficient number, since it is larger than the sum of its proper divisors (45347235075984).

91827890139969 is an frugal number, since it uses more digits than its factorization.

91827890139969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2129498 (or 1064746 counting only the distinct ones).

The product of its (nonzero) digits is 952342272, while the sum is 81.

91827890139969 divided by its sum of digits (81) gives a square (1133677656049 = 1064743²).

The spelling of 91827890139969 in words is "ninety-one trillion, eight hundred twenty-seven billion, eight hundred ninety million, one hundred thirty-nine thousand, nine hundred sixty-nine".