20451002213057 has 4 divisors (see below), whose sum is σ = 22024156229460. Its totient is φ = 18877848196656.

The previous prime is 20451002213053. The next prime is 20451002213069. The reversal of 20451002213057 is 75031220015402.

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 1190174084401 + 19260828128656 = 1090951^2 + 4388716^2 .

It is a cyclic number.

It is not a de Polignac number, because 20451002213057 - 2² = 20451002213053 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20451002213053) 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, 786577008182 + ... + 786577008207.

It is an arithmetic number, because the mean of its divisors is an integer number (5506039057365).

Almost surely, 2^{20451002213057} is an apocalyptic number.

It is an amenable number.

20451002213057 is a deficient number, since it is larger than the sum of its proper divisors (1573154016403).

20451002213057 is a wasteful number, since it uses less digits than its factorization.

20451002213057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1573154016402.

The product of its (nonzero) digits is 16800, while the sum is 32.

Adding to 20451002213057 its reverse (75031220015402), we get a palindrome (95482222228459).

The spelling of 20451002213057 in words is "twenty trillion, four hundred fifty-one billion, two million, two hundred thirteen thousand, fifty-seven".