21511424650 has 48 divisors (see below), whose sum is σ = 40784686488. Its totient is φ = 8439552000.

The previous prime is 21511424647. The next prime is 21511424707. The reversal of 21511424650 is 5642411512.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 177608929 + 21333815721 = 13327^2 + 146061^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 644370 + ... + 676930.

Almost surely, 2^21511424650 is an apocalyptic number.

21511424650 is a deficient number, since it is larger than the sum of its proper divisors (19273261838).

21511424650 is a wasteful number, since it uses less digits than its factorization.

21511424650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32827 (or 32822 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 31.

The spelling of 21511424650 in words is "twenty-one billion, five hundred eleven million, four hundred twenty-four thousand, six hundred fifty".