20667436648 has 8 divisors (see below), whose sum is σ = 38751443730. Its totient is φ = 10333718320.

The previous prime is 20667436633. The next prime is 20667436687. The reversal of 20667436648 is 84663476602.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 13844346244 + 6823090404 = 117662^2 + 82602^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 20667436595 and 20667436604.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1291714783 + ... + 1291714798.

Almost surely, 2^20667436648 is an apocalyptic number.

It is an amenable number.

20667436648 is a deficient number, since it is larger than the sum of its proper divisors (18084007082).

20667436648 is a wasteful number, since it uses less digits than its factorization.

20667436648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2583429587 (or 2583429583 counting only the distinct ones).

The product of its (nonzero) digits is 6967296, while the sum is 52.

The spelling of 20667436648 in words is "twenty billion, six hundred sixty-seven million, four hundred thirty-six thousand, six hundred forty-eight".