51031621641 has 64 divisors (see below), whose sum is σ = 91863023616. Its totient is φ = 24335251200.

The previous prime is 51031621603. The next prime is 51031621643. The reversal of 51031621641 is 14612613015.

It is a happy number.

It is not a de Polignac number, because 51031621641 - 2¹⁰ = 51031620617 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 51031621599 and 51031621608.

It is not an unprimeable number, because it can be changed into a prime (51031621643) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 496600 + ... + 590486.

It is an arithmetic number, because the mean of its divisors is an integer number (1435359744).

Almost surely, 2^51031621641 is an apocalyptic number.

It is an amenable number.

51031621641 is a deficient number, since it is larger than the sum of its proper divisors (40831401975).

51031621641 is a wasteful number, since it uses less digits than its factorization.

51031621641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94102.

The product of its (nonzero) digits is 4320, while the sum is 30.

The spelling of 51031621641 in words is "fifty-one billion, thirty-one million, six hundred twenty-one thousand, six hundred forty-one".