990564632623 has 4 divisors (see below), whose sum is σ = 999822246120. Its totient is φ = 981307019128.

The previous prime is 990564632593. The next prime is 990564632627. The reversal of 990564632623 is 326236465099.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 990564632623 - 2²¹ = 990562535471 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990564632627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4628806588 + ... + 4628806801.

It is an arithmetic number, because the mean of its divisors is an integer number (249955561530).

Almost surely, 2^990564632623 is an apocalyptic number.

990564632623 is a deficient number, since it is larger than the sum of its proper divisors (9257613497).

990564632623 is a wasteful number, since it uses less digits than its factorization.

990564632623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9257613496.

The product of its (nonzero) digits is 12597120, while the sum is 55.

The spelling of 990564632623 in words is "nine hundred ninety billion, five hundred sixty-four million, six hundred thirty-two thousand, six hundred twenty-three".