51751212121 has 8 divisors (see below), whose sum is σ = 59175567360. Its totient is φ = 44334688128.

The previous prime is 51751212091. The next prime is 51751212193. The reversal of 51751212121 is 12121215715.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 51751212121 - 2⁹ = 51751211609 is a prime.

51751212121 is a modest number, since divided by 212121 gives 51751 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 51751212121.

It is not an unprimeable number, because it can be changed into a prime (51751312121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1943641 + ... + 1970086.

It is an arithmetic number, because the mean of its divisors is an integer number (7396945920).

Almost surely, 2^51751212121 is an apocalyptic number.

It is an amenable number.

51751212121 is a deficient number, since it is larger than the sum of its proper divisors (7424355239).

51751212121 is a wasteful number, since it uses less digits than its factorization.

51751212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3915623.

The product of its digits is 1400, while the sum is 28.

Adding to 51751212121 its reverse (12121215715), we get a palindrome (63872427836).

The spelling of 51751212121 in words is "fifty-one billion, seven hundred fifty-one million, two hundred twelve thousand, one hundred twenty-one".