31491664903 has 4 divisors (see below), whose sum is σ = 31492032880. Its totient is φ = 31491296928.

The previous prime is 31491664901. The next prime is 31491664907. The reversal of 31491664903 is 30946619413.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 31491664903 - 2¹ = 31491664901 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31491664901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19126 + ... + 251692.

It is an arithmetic number, because the mean of its divisors is an integer number (7873008220).

Almost surely, 2^31491664903 is an apocalyptic number.

31491664903 is a deficient number, since it is larger than the sum of its proper divisors (367977).

31491664903 is a wasteful number, since it uses less digits than its factorization.

31491664903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 367976.

The product of its (nonzero) digits is 419904, while the sum is 46.

The spelling of 31491664903 in words is "thirty-one billion, four hundred ninety-one million, six hundred sixty-four thousand, nine hundred three".