91521355994001 has 12 divisors (see below), whose sum is σ = 132201822263940. Its totient is φ = 61012248998400.

The previous prime is 91521355993987. The next prime is 91521355994009. The reversal of 91521355994001 is 10049955312519.

91521355994001 is a `hidden beast` number, since 9 + 1 + 5 + 2 + 1 + 3 + 5 + 599 + 40 + 0 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 49410341504001 + 42111014490000 = 7029249^2 + 6489300^2 .

It is not a de Polignac number, because 91521355994001 - 2⁴¹ = 89322332738449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91521355994009) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 165402700 + ... + 165955101.

It is an arithmetic number, because the mean of its divisors is an integer number (11016818521995).

Almost surely, 2^{91521355994001} is an apocalyptic number.

It is an amenable number.

91521355994001 is a deficient number, since it is larger than the sum of its proper divisors (40680466269939).

91521355994001 is a wasteful number, since it uses less digits than its factorization.

91521355994001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331388496 (or 331388493 counting only the distinct ones).

The product of its (nonzero) digits is 2187000, while the sum is 54.

The spelling of 91521355994001 in words is "ninety-one trillion, five hundred twenty-one billion, three hundred fifty-five million, nine hundred ninety-four thousand, one".