31857828986987 has 8 divisors (see below), whose sum is σ = 33731876942496. Its totient is φ = 29983787477632.

The previous prime is 31857828986983. The next prime is 31857828986989. The reversal of 31857828986987 is 78968982875813.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31857828986987 - 2² = 31857828986983 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31857828986981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11709698 + ... + 14171544.

It is an arithmetic number, because the mean of its divisors is an integer number (4216484617812).

Almost surely, 2^{31857828986987} is an apocalyptic number.

31857828986987 is a deficient number, since it is larger than the sum of its proper divisors (1874047955509).

31857828986987 is a wasteful number, since it uses less digits than its factorization.

31857828986987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3223077.

The product of its digits is 23410114560, while the sum is 89.

Adding to 31857828986987 its sum of digits (89), we get a square (31857828987076 = 5644274²).

The spelling of 31857828986987 in words is "thirty-one trillion, eight hundred fifty-seven billion, eight hundred twenty-eight million, nine hundred eighty-six thousand, nine hundred eighty-seven".