91629720 has 192 divisors, whose sum is σ = 366649920. Its totient is φ = 19325952.

The previous prime is 91629719. The next prime is 91629721. The reversal of 91629720 is 2792619.

91629720 is a `hidden beast` number, since 9 + 1 + 629 + 7 + 20 = 666.

It is an interprime number because it is at equal distance from previous prime (91629719) and next prime (91629721).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91629721) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 31362 + ... + 34158.

It is an arithmetic number, because the mean of its divisors is an integer number (1909635).

Almost surely, 2^91629720 is an apocalyptic number.

91629720 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 91629720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (183324960).

91629720 is an abundant number, since it is smaller than the sum of its proper divisors (275020200).

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

91629720 is a wasteful number, since it uses less digits than its factorization.

91629720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2834 (or 2827 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 36.

The square root of 91629720 is about 9572.3414063645. The cubic root of 91629720 is about 450.8292856213.

The spelling of 91629720 in words is "ninety-one million, six hundred twenty-nine thousand, seven hundred twenty".