31143167991 has 24 divisors (see below), whose sum is σ = 49754257280. Its totient is φ = 18647050176.

The previous prime is 31143167989. The next prime is 31143168031. The reversal of 31143167991 is 19976134113.

It is not a de Polignac number, because 31143167991 - 2¹ = 31143167989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31143167911) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3592711 + ... + 3601368.

Almost surely, 2^31143167991 is an apocalyptic number.

31143167991 is a deficient number, since it is larger than the sum of its proper divisors (18611089289).

31143167991 is a wasteful number, since it uses less digits than its factorization.

31143167991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7194135 (or 7194132 counting only the distinct ones).

The product of its digits is 122472, while the sum is 45.

The spelling of 31143167991 in words is "thirty-one billion, one hundred forty-three million, one hundred sixty-seven thousand, nine hundred ninety-one".