31639506109 has 4 divisors (see below), whose sum is σ = 31640407200. Its totient is φ = 31638605020.

The previous prime is 31639506023. The next prime is 31639506131. The reversal of 31639506109 is 90160593613.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90160593613 = 43 ⋅2096757991.

It is a cyclic number.

It is not a de Polignac number, because 31639506109 - 2¹⁹ = 31638981821 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 (31639506139) 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, 395647 + ... + 468844.

It is an arithmetic number, because the mean of its divisors is an integer number (7910101800).

Almost surely, 2^31639506109 is an apocalyptic number.

It is an amenable number.

31639506109 is a deficient number, since it is larger than the sum of its proper divisors (901091).

31639506109 is an equidigital number, since it uses as much as digits as its factorization.

31639506109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 901090.

The product of its (nonzero) digits is 131220, while the sum is 43.

The spelling of 31639506109 in words is "thirty-one billion, six hundred thirty-nine million, five hundred six thousand, one hundred nine".