91619419969 has 27 divisors (see below), whose sum is σ = 117177189633. Its totient is φ = 71373594600.

The previous prime is 91619419961. The next prime is 91619419981. The reversal of 91619419969 is 96991491619.

It is a happy number.

The square root of 91619419969 is 302687.

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

It is not a de Polignac number, because 91619419969 - 2³ = 91619419961 is a prime.

It is a super-2 number, since 2×91619419969² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 91619419969.

It is not an unprimeable number, because it can be changed into a prime (91619419961) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 23304934 + ... + 23308864.

Almost surely, 2^91619419969 is an apocalyptic number.

91619419969 is the 302687-th square number.

91619419969 is the 151344-th centered octagonal number.

It is an amenable number.

91619419969 is a deficient number, since it is larger than the sum of its proper divisors (25557769664).

91619419969 is an frugal number, since it uses more digits than its factorization.

91619419969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7898 (or 3949 counting only the distinct ones).

The product of its digits is 8503056, while the sum is 64.

Multiplying 91619419969 by its sum of digits (64), we get a square (5863642878016 = 2421496²).

The spelling of 91619419969 in words is "ninety-one billion, six hundred nineteen million, four hundred nineteen thousand, nine hundred sixty-nine".