91561600 has 192 divisors, whose sum is σ = 254983680. Its totient is φ = 32256000.

The previous prime is 91561583. The next prime is 91561601. The reversal of 91561600 is 616519.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91561601) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1289565 + ... + 1289635.

It is an arithmetic number, because the mean of its divisors is an integer number (1328040).

Almost surely, 2^91561600 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 91561600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127491840).

91561600 is an abundant number, since it is smaller than the sum of its proper divisors (163422080).

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

91561600 is a wasteful number, since it uses less digits than its factorization.

91561600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 91561600 is about 9568.7825766918. The cubic root of 91561600 is about 450.7175383832.

The spelling of 91561600 in words is "ninety-one million, five hundred sixty-one thousand, six hundred".