20950451913157 has 4 divisors (see below), whose sum is σ = 22562025137260. Its totient is φ = 19338878689056.

The previous prime is 20950451913109. The next prime is 20950451913161. The reversal of 20950451913157 is 75131915405902.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4365366707716 + 16585085205441 = 2089346^2 + 4072479^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20950451913157 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 (20950451913857) 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, 805786612032 + ... + 805786612057.

It is an arithmetic number, because the mean of its divisors is an integer number (5640506284315).

Almost surely, 2^{20950451913157} is an apocalyptic number.

It is an amenable number.

20950451913157 is a deficient number, since it is larger than the sum of its proper divisors (1611573224103).

20950451913157 is a wasteful number, since it uses less digits than its factorization.

20950451913157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1611573224102.

The product of its (nonzero) digits is 1701000, while the sum is 52.

The spelling of 20950451913157 in words is "twenty trillion, nine hundred fifty billion, four hundred fifty-one million, nine hundred thirteen thousand, one hundred fifty-seven".