51657558237421 has 8 divisors (see below), whose sum is σ = 53056509291360. Its totient is φ = 50258754595728.

The previous prime is 51657558237403. The next prime is 51657558237463. The reversal of 51657558237421 is 12473285575615.

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 51657558237421 - 2²³ = 51657549848813 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51657558237421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51657558237121) 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, 36142531 + ... + 37544608.

It is an arithmetic number, because the mean of its divisors is an integer number (6632063661420).

Almost surely, 2^{51657558237421} is an apocalyptic number.

It is an amenable number.

51657558237421 is a deficient number, since it is larger than the sum of its proper divisors (1398951053939).

51657558237421 is a wasteful number, since it uses less digits than its factorization.

51657558237421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73706123.

The product of its digits is 70560000, while the sum is 61.

The spelling of 51657558237421 in words is "fifty-one trillion, six hundred fifty-seven billion, five hundred fifty-eight million, two hundred thirty-seven thousand, four hundred twenty-one".