31380681 has 8 divisors (see below), whose sum is σ = 41870304. Its totient is φ = 20905760.

The previous prime is 31380677. The next prime is 31380683. The reversal of 31380681 is 18608313.

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 31380681 - 2² = 31380677 is a prime.

It is a super-2 number, since 2×31380681² = 1969494280047522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (31380683) 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, 3085 + ... + 8501.

It is an arithmetic number, because the mean of its divisors is an integer number (5233788).

Almost surely, 2^31380681 is an apocalyptic number.

It is an amenable number.

31380681 is a deficient number, since it is larger than the sum of its proper divisors (10489623).

31380681 is a wasteful number, since it uses less digits than its factorization.

31380681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7351.

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 31380681 is about 5601.8462135264. The cubic root of 31380681 is about 315.4187125188.

Adding to 31380681 its reverse (18608313), we get a palindrome (49988994).

The spelling of 31380681 in words is "thirty-one million, three hundred eighty thousand, six hundred eighty-one".