20605660641 has 12 divisors (see below), whose sum is σ = 29766028032. Its totient is φ = 13736047416.

The previous prime is 20605660637. The next prime is 20605660651. The reversal of 20605660641 is 14606650602.

It is a happy number.

20605660641 is a `hidden beast` number, since 2 + 0 + 6 + 0 + 5 + 6 + 6 + 0 + 641 = 666.

It is not a de Polignac number, because 20605660641 - 2² = 20605660637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20605660596 and 20605660605.

It is not an unprimeable number, because it can be changed into a prime (20605660631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45520 + ... + 208046.

It is an arithmetic number, because the mean of its divisors is an integer number (2480502336).

Almost surely, 2^20605660641 is an apocalyptic number.

It is an amenable number.

20605660641 is a deficient number, since it is larger than the sum of its proper divisors (9160367391).

20605660641 is a wasteful number, since it uses less digits than its factorization.

20605660641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176620 (or 176617 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The spelling of 20605660641 in words is "twenty billion, six hundred five million, six hundred sixty thousand, six hundred forty-one".