91051520 has 80 divisors (see below), whose sum is σ = 249546528. Its totient is φ = 31211520.

The previous prime is 91051517. The next prime is 91051537. The reversal of 91051520 is 2515019.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15380 + ... + 20460.

Almost surely, 2^91051520 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 91051520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124773264).

91051520 is an abundant number, since it is smaller than the sum of its proper divisors (158495008).

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

91051520 is an equidigital number, since it uses as much as digits as its factorization.

91051520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5111 (or 5095 counting only the distinct ones).

The product of its (nonzero) digits is 450, while the sum is 23.

The square root of 91051520 is about 9542.0920138091. The cubic root of 91051520 is about 449.8790127417.

Adding to 91051520 its reverse (2515019), we get a palindrome (93566539).

The spelling of 91051520 in words is "ninety-one million, fifty-one thousand, five hundred twenty".