20699405637 has 4 divisors (see below), whose sum is σ = 27599207520. Its totient is φ = 13799603756.

The previous prime is 20699405627. The next prime is 20699405669. The reversal of 20699405637 is 73650499602.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20699405637 - 2¹¹ = 20699403589 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20699405637.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20699405627) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3449900937 + ... + 3449900942.

It is an arithmetic number, because the mean of its divisors is an integer number (6899801880).

Almost surely, 2^20699405637 is an apocalyptic number.

It is an amenable number.

20699405637 is a deficient number, since it is larger than the sum of its proper divisors (6899801883).

20699405637 is an equidigital number, since it uses as much as digits as its factorization.

20699405637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6899801882.

The product of its (nonzero) digits is 2449440, while the sum is 51.

The spelling of 20699405637 in words is "twenty billion, six hundred ninety-nine million, four hundred five thousand, six hundred thirty-seven".