31000380 has 24 divisors (see below), whose sum is σ = 86801232. Its totient is φ = 8266752.

The previous prime is 31000351. The next prime is 31000397. The reversal of 31000380 is 8300013.

It is a super-2 number, since 2×31000380² = 1922047120288800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 258277 + ... + 258396.

It is an arithmetic number, because the mean of its divisors is an integer number (3616718).

Almost surely, 2^31000380 is an apocalyptic number.

31000380 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31000380 is an abundant number, since it is smaller than the sum of its proper divisors (55800852).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31000380 is a wasteful number, since it uses less digits than its factorization.

31000380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 516685 (or 516683 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 31000380 is about 5567.7984877328. The cubic root of 31000380 is about 314.1393488088.

Adding to 31000380 its reverse (8300013), we get a palindrome (39300393).

The spelling of 31000380 in words is "thirty-one million, three hundred eighty", and thus it is an aban number.