21900672390 has 64 divisors (see below), whose sum is σ = 52920241920. Its totient is φ = 5800417920.

The previous prime is 21900672389. The next prime is 21900672397. The reversal of 21900672390 is 9327600912.

It is a super-2 number, since 2×21900672390² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21900672397) 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 31 ways as a sum of consecutive naturals, for example, 5140081 + ... + 5144339.

It is an arithmetic number, because the mean of its divisors is an integer number (826878780).

Almost surely, 2^21900672390 is an apocalyptic number.

21900672390 is an abundant number, since it is smaller than the sum of its proper divisors (31019569530).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21900672390 is a wasteful number, since it uses less digits than its factorization.

21900672390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5397.

The product of its (nonzero) digits is 40824, while the sum is 39.

The spelling of 21900672390 in words is "twenty-one billion, nine hundred million, six hundred seventy-two thousand, three hundred ninety".