90644537 has 4 divisors (see below), whose sum is σ = 90803856. Its totient is φ = 90485220.

The previous prime is 90644479. The next prime is 90644539. The reversal of 90644537 is 73544609.

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 90644537 - 2¹⁸ = 90382393 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 90644537.

It is not an unprimeable number, because it can be changed into a prime (90644539) 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, 78803 + ... + 79944.

It is an arithmetic number, because the mean of its divisors is an integer number (22700964).

Almost surely, 2^90644537 is an apocalyptic number.

It is an amenable number.

90644537 is a deficient number, since it is larger than the sum of its proper divisors (159319).

90644537 is a wasteful number, since it uses less digits than its factorization.

90644537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159318.

The product of its (nonzero) digits is 90720, while the sum is 38.

The square root of 90644537 is about 9520.7424605437. The cubic root of 90644537 is about 449.2077203173.

The spelling of 90644537 in words is "ninety million, six hundred forty-four thousand, five hundred thirty-seven".