20781605692 has 6 divisors (see below), whose sum is σ = 36367809968. Its totient is φ = 10390802844.

The previous prime is 20781605659. The next prime is 20781605701. The reversal of 20781605692 is 29650618702.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2597700708 + ... + 2597700715.

Almost surely, 2^20781605692 is an apocalyptic number.

It is an amenable number.

20781605692 is a deficient number, since it is larger than the sum of its proper divisors (15586204276).

20781605692 is a wasteful number, since it uses less digits than its factorization.

20781605692 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5195401427 (or 5195401425 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 46.

The spelling of 20781605692 in words is "twenty billion, seven hundred eighty-one million, six hundred five thousand, six hundred ninety-two".