51454861421 has 4 divisors (see below), whose sum is σ = 51464744700. Its totient is φ = 51444978144.

The previous prime is 51454861411. The next prime is 51454861427. The reversal of 51454861421 is 12416845415.

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 25206325225 + 26248536196 = 158765^2 + 162014^2 .

It is a cyclic number.

It is not a de Polignac number, because 51454861421 - 2⁶ = 51454861357 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51454861427) 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, 4933826 + ... + 4944243.

It is an arithmetic number, because the mean of its divisors is an integer number (12866186175).

Almost surely, 2^51454861421 is an apocalyptic number.

It is an amenable number.

51454861421 is a deficient number, since it is larger than the sum of its proper divisors (9883279).

51454861421 is an equidigital number, since it uses as much as digits as its factorization.

51454861421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9883278.

The product of its digits is 153600, while the sum is 41.

The spelling of 51454861421 in words is "fifty-one billion, four hundred fifty-four million, eight hundred sixty-one thousand, four hundred twenty-one".