91405553 has 4 divisors (see below), whose sum is σ = 93350400. Its totient is φ = 89460708.

The previous prime is 91405541. The next prime is 91405571. The reversal of 91405553 is 35550419.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 91405553 - 2⁸ = 91405297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91405513) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 972353 + ... + 972446.

It is an arithmetic number, because the mean of its divisors is an integer number (23337600).

Almost surely, 2^91405553 is an apocalyptic number.

It is an amenable number.

91405553 is a deficient number, since it is larger than the sum of its proper divisors (1944847).

91405553 is a wasteful number, since it uses less digits than its factorization.

91405553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1944846.

The product of its (nonzero) digits is 13500, while the sum is 32.

The square root of 91405553 is about 9560.6251364647. The cubic root of 91405553 is about 450.4613425053.

The spelling of 91405553 in words is "ninety-one million, four hundred five thousand, five hundred fifty-three".