31748789 has 4 divisors (see below), whose sum is σ = 31887660. Its totient is φ = 31609920.

The previous prime is 31748777. The next prime is 31748831. The reversal of 31748789 is 98784713.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17056900 + 14691889 = 4130^2 + 3833^2 .

It is a cyclic number.

It is not a de Polignac number, because 31748789 - 2²⁰ = 30700213 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 (31748729) 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, 69092 + ... + 69549.

It is an arithmetic number, because the mean of its divisors is an integer number (7971915).

Almost surely, 2^31748789 is an apocalyptic number.

It is an amenable number.

31748789 is a deficient number, since it is larger than the sum of its proper divisors (138871).

31748789 is a wasteful number, since it uses less digits than its factorization.

31748789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138870.

The product of its digits is 338688, while the sum is 47.

The square root of 31748789 is about 5634.6063748943. The cubic root of 31748789 is about 316.6472506409.

The spelling of 31748789 in words is "thirty-one million, seven hundred forty-eight thousand, seven hundred eighty-nine".