20641662645 has 32 divisors (see below), whose sum is σ = 33430672512. Its totient is φ = 10874806272.

The previous prime is 20641662631. The next prime is 20641662661. The reversal of 20641662645 is 54626614602.

It is not a de Polignac number, because 20641662645 - 2¹⁸ = 20641400501 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20641662597 and 20641662606.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 548349 + ... + 584781.

It is an arithmetic number, because the mean of its divisors is an integer number (1044708516).

Almost surely, 2^20641662645 is an apocalyptic number.

It is an amenable number.

20641662645 is a deficient number, since it is larger than the sum of its proper divisors (12789009867).

20641662645 is a wasteful number, since it uses less digits than its factorization.

20641662645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36901.

The product of its (nonzero) digits is 414720, while the sum is 42.

The spelling of 20641662645 in words is "twenty billion, six hundred forty-one million, six hundred sixty-two thousand, six hundred forty-five".