74317731781 has 2 divisors, whose sum is σ = 74317731782. Its totient is φ = 74317731780.

The previous prime is 74317731757. The next prime is 74317731791. The reversal of 74317731781 is 18713771347.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63367992900 + 10949738881 = 251730^2 + 104641^2 .

It is a cyclic number.

It is not a de Polignac number, because 74317731781 - 2¹³ = 74317723589 is a prime.

It is a super-2 number, since 2×74317731781² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (74317731701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37158865890 + 37158865891.

It is an arithmetic number, because the mean of its divisors is an integer number (37158865891).

Almost surely, 2^74317731781 is an apocalyptic number.

It is an amenable number.

74317731781 is a deficient number, since it is larger than the sum of its proper divisors (1).

74317731781 is an equidigital number, since it uses as much as digits as its factorization.

74317731781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 691488, while the sum is 49.

The spelling of 74317731781 in words is "seventy-four billion, three hundred seventeen million, seven hundred thirty-one thousand, seven hundred eighty-one".