91993616 has 80 divisors (see below), whose sum is σ = 216319488. Its totient is φ = 37324800.

The previous prime is 91993609. The next prime is 91993619. The reversal of 91993616 is 61639919.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91993619) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70280 + ... + 71576.

Almost surely, 2^91993616 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91993616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108159744).

91993616 is an abundant number, since it is smaller than the sum of its proper divisors (124325872).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91993616 is a wasteful number, since it uses less digits than its factorization.

91993616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1360 (or 1354 counting only the distinct ones).

The product of its digits is 78732, while the sum is 44.

The square root of 91993616 is about 9591.3302518472. The cubic root of 91993616 is about 451.4253014008.

The spelling of 91993616 in words is "ninety-one million, nine hundred ninety-three thousand, six hundred sixteen".