20645338964 has 6 divisors (see below), whose sum is σ = 36129343194. Its totient is φ = 10322669480.

The previous prime is 20645338963. The next prime is 20645339017. The reversal of 20645338964 is 46983354602.

It can be written as a sum of positive squares in only one way, i.e., 17564200900 + 3081138064 = 132530^2 + 55508^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20645338963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2580667367 + ... + 2580667374.

It is an arithmetic number, because the mean of its divisors is an integer number (6021557199).

Almost surely, 2^20645338964 is an apocalyptic number.

It is an amenable number.

20645338964 is a deficient number, since it is larger than the sum of its proper divisors (15484004230).

20645338964 is a wasteful number, since it uses less digits than its factorization.

20645338964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5161334745 (or 5161334743 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 50.

The spelling of 20645338964 in words is "twenty billion, six hundred forty-five million, three hundred thirty-eight thousand, nine hundred sixty-four".