31345021 has 8 divisors (see below), whose sum is σ = 33010560. Its totient is φ = 29704752.

The previous prime is 31345019. The next prime is 31345049. The reversal of 31345021 is 12054313.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31345021 - 2¹ = 31345019 is a prime.

It is a super-3 number, since 3×31345021³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31345021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31345001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3745 + ... + 8758.

It is an arithmetic number, because the mean of its divisors is an integer number (4126320).

Almost surely, 2^31345021 is an apocalyptic number.

It is an amenable number.

31345021 is a deficient number, since it is larger than the sum of its proper divisors (1665539).

31345021 is a wasteful number, since it uses less digits than its factorization.

31345021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12635.

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 31345021 is about 5598.6624295451. The cubic root of 31345021 is about 315.2991899954.

Adding to 31345021 its reverse (12054313), we get a palindrome (43399334).

The spelling of 31345021 in words is "thirty-one million, three hundred forty-five thousand, twenty-one".