20664611539 has 16 divisors (see below), whose sum is σ = 24341425920. Its totient is φ = 17295132960.

The previous prime is 20664611521. The next prime is 20664611567. The reversal of 20664611539 is 93511646602.

It is a cyclic number.

It is not a de Polignac number, because 20664611539 - 2¹⁹ = 20664087251 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20664611495 and 20664611504.

It is not an unprimeable number, because it can be changed into a prime (20664611599) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 136447 + ... + 244840.

It is an arithmetic number, because the mean of its divisors is an integer number (1521339120).

Almost surely, 2^20664611539 is an apocalyptic number.

20664611539 is a deficient number, since it is larger than the sum of its proper divisors (3676814381).

20664611539 is a wasteful number, since it uses less digits than its factorization.

20664611539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381690.

The product of its (nonzero) digits is 233280, while the sum is 43.

The spelling of 20664611539 in words is "twenty billion, six hundred sixty-four million, six hundred eleven thousand, five hundred thirty-nine".