20126402712251 has 4 divisors (see below), whose sum is σ = 21956075686104. Its totient is φ = 18296729738400.

The previous prime is 20126402712223. The next prime is 20126402712277. The reversal of 20126402712251 is 15221720462102.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20126402712251 is a prime.

It is a super-2 number, since 2×20126402712251² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20126402712751) 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, 914836486910 + ... + 914836486931.

It is an arithmetic number, because the mean of its divisors is an integer number (5489018921526).

Almost surely, 2^{20126402712251} is an apocalyptic number.

20126402712251 is a deficient number, since it is larger than the sum of its proper divisors (1829672973853).

20126402712251 is a wasteful number, since it uses less digits than its factorization.

20126402712251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1829672973852.

The product of its (nonzero) digits is 26880, while the sum is 35.

The spelling of 20126402712251 in words is "twenty trillion, one hundred twenty-six billion, four hundred two million, seven hundred twelve thousand, two hundred fifty-one".