31478691257 has 16 divisors (see below), whose sum is σ = 36211931280. Its totient is φ = 27105964032.

The previous prime is 31478691247. The next prime is 31478691301. The reversal of 31478691257 is 75219687413.

It can be written as a sum of positive squares in 8 ways, for example, as 12719553961 + 18759137296 = 112781^2 + 136964^2 .

It is a cyclic number.

It is not a de Polignac number, because 31478691257 - 2⁶ = 31478691193 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31478691199 and 31478691208.

It is not an unprimeable number, because it can be changed into a prime (31478691217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 605282 + ... + 655227.

It is an arithmetic number, because the mean of its divisors is an integer number (2263245705).

Almost surely, 2^31478691257 is an apocalyptic number.

It is an amenable number.

31478691257 is a deficient number, since it is larger than the sum of its proper divisors (4733240023).

31478691257 is a wasteful number, since it uses less digits than its factorization.

31478691257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1260652.

The product of its digits is 2540160, while the sum is 53.

The spelling of 31478691257 in words is "thirty-one billion, four hundred seventy-eight million, six hundred ninety-one thousand, two hundred fifty-seven".