31222397 has 4 divisors (see below), whose sum is σ = 31249596. Its totient is φ = 31195200.

The previous prime is 31222393. The next prime is 31222427. The reversal of 31222397 is 79322213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79322213 = 2131 ⋅37223.

It can be written as a sum of positive squares in 2 ways, for example, as 1038361 + 30184036 = 1019^2 + 5494^2 .

It is a cyclic number.

It is not a de Polignac number, because 31222397 - 2² = 31222393 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 (31222391) 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, 11798 + ... + 14199.

It is an arithmetic number, because the mean of its divisors is an integer number (7812399).

Almost surely, 2^31222397 is an apocalyptic number.

It is an amenable number.

31222397 is a deficient number, since it is larger than the sum of its proper divisors (27199).

31222397 is a wasteful number, since it uses less digits than its factorization.

31222397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27198.

The product of its digits is 4536, while the sum is 29.

The square root of 31222397 is about 5587.7005109437. The cubic root of 31222397 is about 314.8874948860.

The spelling of 31222397 in words is "thirty-one million, two hundred twenty-two thousand, three hundred ninety-seven".