21152256490 has 8 divisors (see below), whose sum is σ = 38074061700. Its totient is φ = 8460902592.

The previous prime is 21152256479. The next prime is 21152256529. The reversal of 21152256490 is 9465225112.

It can be written as a sum of positive squares in 2 ways, for example, as 20698864641 + 453391849 = 143871^2 + 21293^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1057612815 + ... + 1057612834.

Almost surely, 2^21152256490 is an apocalyptic number.

21152256490 is a deficient number, since it is larger than the sum of its proper divisors (16921805210).

21152256490 is a wasteful number, since it uses less digits than its factorization.

21152256490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2115225656.

The product of its (nonzero) digits is 43200, while the sum is 37.

The spelling of 21152256490 in words is "twenty-one billion, one hundred fifty-two million, two hundred fifty-six thousand, four hundred ninety".