20721624486 has 16 divisors (see below), whose sum is σ = 42026957568. Its totient is φ = 6809923400.

The previous prime is 20721624481. The next prime is 20721624493. The reversal of 20721624486 is 68442612702.

It is a happy number.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20721624481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24320730 + ... + 24321581.

It is an arithmetic number, because the mean of its divisors is an integer number (2626684848).

Almost surely, 2^20721624486 is an apocalyptic number.

20721624486 is an abundant number, since it is smaller than the sum of its proper divisors (21305333082).

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

20721624486 is a wasteful number, since it uses less digits than its factorization.

20721624486 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48642387.

The product of its (nonzero) digits is 258048, while the sum is 42.

The spelling of 20721624486 in words is "twenty billion, seven hundred twenty-one million, six hundred twenty-four thousand, four hundred eighty-six".