91642320 has 640 divisors, whose sum is σ = 428544000. Its totient is φ = 17418240.

The previous prime is 91642307. The next prime is 91642333. The reversal of 91642320 is 2324619.

It is an interprime number because it is at equal distance from previous prime (91642307) and next prime (91642333).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 3160066 + ... + 3160094.

It is an arithmetic number, because the mean of its divisors is an integer number (669600).

Almost surely, 2^91642320 is an apocalyptic number.

91642320 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91642320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (214272000).

91642320 is an abundant number, since it is smaller than the sum of its proper divisors (336901680).

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

91642320 is a wasteful number, since it uses less digits than its factorization.

91642320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 91642320 is about 9572.9995299279. Note that the first 3 decimals coincide. The cubic root of 91642320 is about 450.8499491813.

Adding to 91642320 its reverse (2324619), we get a palindrome (93966939).

It can be divided in two parts, 91 and 642320, that added together give a triangular number (642411 = T₁₁₃₃).

The spelling of 91642320 in words is "ninety-one million, six hundred forty-two thousand, three hundred twenty".