20856501151 has 4 divisors (see below), whose sum is σ = 20897965872. Its totient is φ = 20815036432.

The previous prime is 20856501139. The next prime is 20856501163. The reversal of 20856501151 is 15110565802.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (20856501139) and next prime (20856501163).

It is a cyclic number.

It is not a de Polignac number, because 20856501151 - 2⁷ = 20856501023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20856501181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20731606 + ... + 20732611.

It is an arithmetic number, because the mean of its divisors is an integer number (5224491468).

Almost surely, 2^20856501151 is an apocalyptic number.

20856501151 is a deficient number, since it is larger than the sum of its proper divisors (41464721).

20856501151 is an equidigital number, since it uses as much as digits as its factorization.

20856501151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41464720.

The product of its (nonzero) digits is 12000, while the sum is 34.

The spelling of 20856501151 in words is "twenty billion, eight hundred fifty-six million, five hundred one thousand, one hundred fifty-one".