20666108772 has 24 divisors (see below), whose sum is σ = 53578800800. Its totient is φ = 6888702888.

The previous prime is 20666108767. The next prime is 20666108777. The reversal of 20666108772 is 27780166602.

It is an interprime number because it is at equal distance from previous prime (20666108767) and next prime (20666108777).

It is a super-2 number, since 2×20666108772² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20666108777) 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, 95676322 + ... + 95676537.

Almost surely, 2^20666108772 is an apocalyptic number.

It is an amenable number.

20666108772 is an abundant number, since it is smaller than the sum of its proper divisors (32912692028).

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

20666108772 is a wasteful number, since it uses less digits than its factorization.

20666108772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191352872 (or 191352864 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 45.

The spelling of 20666108772 in words is "twenty billion, six hundred sixty-six million, one hundred eight thousand, seven hundred seventy-two".