91919481 has 4 divisors (see below), whose sum is σ = 122559312. Its totient is φ = 61279652.

The previous prime is 91919479. The next prime is 91919501. The reversal of 91919481 is 18491919.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 91919481 - 2¹ = 91919479 is a prime.

It is a super-2 number, since 2×91919481² = 16898381974618722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91919461) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15319911 + ... + 15319916.

It is an arithmetic number, because the mean of its divisors is an integer number (30639828).

Almost surely, 2^91919481 is an apocalyptic number.

It is an amenable number.

91919481 is a deficient number, since it is larger than the sum of its proper divisors (30639831).

91919481 is a wasteful number, since it uses less digits than its factorization.

91919481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30639830.

The product of its digits is 23328, while the sum is 42.

The square root of 91919481 is about 9587.4647848115. The cubic root of 91919481 is about 451.3040052716.

The spelling of 91919481 in words is "ninety-one million, nine hundred nineteen thousand, four hundred eighty-one".