31306404 has 48 divisors (see below), whose sum is σ = 78704640. Its totient is φ = 9657120.

The previous prime is 31306393. The next prime is 31306417. The reversal of 31306404 is 40460313.

It is a super-2 number, since 2×31306404² = 1960181862822432, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6727 + ... + 10385.

It is an arithmetic number, because the mean of its divisors is an integer number (1639680).

Almost surely, 2^31306404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31306404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39352320).

31306404 is an abundant number, since it is smaller than the sum of its proper divisors (47398236).

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

31306404 is a wasteful number, since it uses less digits than its factorization.

31306404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3720 (or 3718 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 31306404 is about 5595.2125964971. The cubic root of 31306404 is about 315.1696541383.

Adding to 31306404 its reverse (40460313), we get a palindrome (71766717).

The spelling of 31306404 in words is "thirty-one million, three hundred six thousand, four hundred four".