90400644889 has 3 divisors (see below), whose sum is σ = 90400945557. Its totient is φ = 90400344222.

The previous prime is 90400644877. The next prime is 90400644953. The reversal of 90400644889 is 98844600409.

The square root of 90400644889 is 300667.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 98844600409 = 17299 ⋅5713891.

It is not a de Polignac number, because 90400644889 - 2²¹ = 90398547737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90400644839) 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 2 ways as a sum of consecutive naturals, for example, 150334 + ... + 451000.

It is an arithmetic number, because the mean of its divisors is an integer number (30133648519).

Almost surely, 2^90400644889 is an apocalyptic number.

90400644889 is the 300667-th square number.

90400644889 is the 150334-th centered octagonal number.

It is an amenable number.

90400644889 is a deficient number, since it is larger than the sum of its proper divisors (300668).

90400644889 is an frugal number, since it uses more digits than its factorization.

90400644889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 601334 (or 300667 counting only the distinct ones).

The product of its (nonzero) digits is 1990656, while the sum is 52.

The spelling of 90400644889 in words is "ninety billion, four hundred million, six hundred forty-four thousand, eight hundred eighty-nine".