31280189 has 4 divisors (see below), whose sum is σ = 31472256. Its totient is φ = 31088124.

The previous prime is 31280177. The next prime is 31280191. The reversal of 31280189 is 98108213.

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.

It is a cyclic number.

It is not a de Polignac number, because 31280189 - 2⁸ = 31279933 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 (31280149) 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, 95789 + ... + 96114.

It is an arithmetic number, because the mean of its divisors is an integer number (7868064).

Almost surely, 2^31280189 is an apocalyptic number.

It is an amenable number.

31280189 is a deficient number, since it is larger than the sum of its proper divisors (192067).

31280189 is a wasteful number, since it uses less digits than its factorization.

31280189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192066.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 31280189 is about 5592.8694781838. The cubic root of 31280189 is about 315.0816585138.

The spelling of 31280189 in words is "thirty-one million, two hundred eighty thousand, one hundred eighty-nine".