20566668015 has 32 divisors (see below), whose sum is σ = 37413277440. Its totient is φ = 10713796128.

The previous prime is 20566668013. The next prime is 20566668019. The reversal of 20566668015 is 51086666502.

It is a happy number.

It is not a de Polignac number, because 20566668015 - 2¹ = 20566668013 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20566668013) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1765657 + ... + 1777266.

It is an arithmetic number, because the mean of its divisors is an integer number (1169164920).

Almost surely, 2^20566668015 is an apocalyptic number.

20566668015 is a deficient number, since it is larger than the sum of its proper divisors (16846609425).

20566668015 is a wasteful number, since it uses less digits than its factorization.

20566668015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3542980 (or 3542974 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The spelling of 20566668015 in words is "twenty billion, five hundred sixty-six million, six hundred sixty-eight thousand, fifteen".