20651651049 has 4 divisors (see below), whose sum is σ = 27535534736. Its totient is φ = 13767767364.

The previous prime is 20651651039. The next prime is 20651651081. The reversal of 20651651049 is 94015615602.

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 not a de Polignac number, because 20651651049 - 2¹⁹ = 20651126761 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20651650998 and 20651651016.

It is not an unprimeable number, because it can be changed into a prime (20651651039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3441941839 + ... + 3441941844.

It is an arithmetic number, because the mean of its divisors is an integer number (6883883684).

Almost surely, 2^20651651049 is an apocalyptic number.

It is an amenable number.

20651651049 is a deficient number, since it is larger than the sum of its proper divisors (6883883687).

20651651049 is an equidigital number, since it uses as much as digits as its factorization.

20651651049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6883883686.

The product of its (nonzero) digits is 64800, while the sum is 39.

The spelling of 20651651049 in words is "twenty billion, six hundred fifty-one million, six hundred fifty-one thousand, forty-nine".