31319442729 has 9 divisors (see below), whose sum is σ = 45239961949. Its totient is φ = 20879274540.

The previous prime is 31319442709. The next prime is 31319442731. The reversal of 31319442729 is 92724491313.

The square root of 31319442729 is 176973.

It is a perfect power (a square), and thus also a powerful number.

31319442729 is a `hidden beast` number, since 3 + 13 + 194 + 427 + 29 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 31319442729 - 2¹³ = 31319434537 is a prime.

It is a super-2 number, since 2×31319442729² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (31319442709) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 501424 + ... + 560414.

Almost surely, 2^31319442729 is an apocalyptic number.

31319442729 is the 176973-rd square number.

31319442729 is the 88487-th centered octagonal number.

It is an amenable number.

31319442729 is a deficient number, since it is larger than the sum of its proper divisors (13920519220).

31319442729 is an frugal number, since it uses more digits than its factorization.

31319442729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117988 (or 58994 counting only the distinct ones).

The product of its digits is 326592, while the sum is 45.

The spelling of 31319442729 in words is "thirty-one billion, three hundred nineteen million, four hundred forty-two thousand, seven hundred twenty-nine".