51421056197 has 4 divisors (see below), whose sum is σ = 58766921376. Its totient is φ = 44075191020.

The previous prime is 51421056161. The next prime is 51421056227. The reversal of 51421056197 is 79165012415.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 51421056197 - 2⁸ = 51421055941 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 (51421056997) 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, 3672932579 + ... + 3672932592.

It is an arithmetic number, because the mean of its divisors is an integer number (14691730344).

Almost surely, 2^51421056197 is an apocalyptic number.

It is an amenable number.

51421056197 is a deficient number, since it is larger than the sum of its proper divisors (7345865179).

51421056197 is an equidigital number, since it uses as much as digits as its factorization.

51421056197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7345865178.

The product of its (nonzero) digits is 75600, while the sum is 41.

The spelling of 51421056197 in words is "fifty-one billion, four hundred twenty-one million, fifty-six thousand, one hundred ninety-seven".