31361389 has 4 divisors (see below), whose sum is σ = 31388256. Its totient is φ = 31334524.

The previous prime is 31361387. The next prime is 31361399. The reversal of 31361389 is 98316313.

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: 98316313 = 1229 ⋅79997.

It is a cyclic number.

It is not a de Polignac number, because 31361389 - 2¹ = 31361387 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 (31361387) 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, 11599 + ... + 14044.

It is an arithmetic number, because the mean of its divisors is an integer number (7847064).

Almost surely, 2^31361389 is an apocalyptic number.

It is an amenable number.

31361389 is a deficient number, since it is larger than the sum of its proper divisors (26867).

31361389 is a wasteful number, since it uses less digits than its factorization.

31361389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26866.

The product of its digits is 11664, while the sum is 34.

The square root of 31361389 is about 5600.1240164839. The cubic root of 31361389 is about 315.3540622838.

The spelling of 31361389 in words is "thirty-one million, three hundred sixty-one thousand, three hundred eighty-nine".