75631076721 has 6 divisors (see below), whose sum is σ = 109244888610. Its totient is φ = 50420717808.

The previous prime is 75631076699. The next prime is 75631076761. The reversal of 75631076721 is 12767013657.

75631076721 is a `hidden beast` number, since 7 + 5 + 631 + 0 + 7 + 6 + 7 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 40376883600 + 35254193121 = 200940^2 + 187761^2 .

It is not a de Polignac number, because 75631076721 - 2⁶ = 75631076657 is a prime.

It is a super-2 number, since 2×75631076721² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (75631076761) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4201726476 + ... + 4201726493.

It is an arithmetic number, because the mean of its divisors is an integer number (18207481435).

Almost surely, 2^75631076721 is an apocalyptic number.

It is an amenable number.

75631076721 is a deficient number, since it is larger than the sum of its proper divisors (33613811889).

75631076721 is a wasteful number, since it uses less digits than its factorization.

75631076721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8403452975 (or 8403452972 counting only the distinct ones).

The product of its (nonzero) digits is 370440, while the sum is 45.

The spelling of 75631076721 in words is "seventy-five billion, six hundred thirty-one million, seventy-six thousand, seven hundred twenty-one".