20571509963 has 4 divisors (see below), whose sum is σ = 20584360728. Its totient is φ = 20558659200.

The previous prime is 20571509953. The next prime is 20571509989. The reversal of 20571509963 is 36990517502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20571509963 - 2⁶ = 20571509899 is a prime.

It is a super-2 number, since 2×20571509963² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20571509953) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6422981 + ... + 6426182.

It is an arithmetic number, because the mean of its divisors is an integer number (5146090182).

Almost surely, 2^20571509963 is an apocalyptic number.

20571509963 is a deficient number, since it is larger than the sum of its proper divisors (12850765).

20571509963 is a wasteful number, since it uses less digits than its factorization.

20571509963 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12850764.

The product of its (nonzero) digits is 510300, while the sum is 47.

The spelling of 20571509963 in words is "twenty billion, five hundred seventy-one million, five hundred nine thousand, nine hundred sixty-three".