31204540 has 12 divisors (see below), whose sum is σ = 65529576. Its totient is φ = 12481808.

The previous prime is 31204531. The next prime is 31204549. The reversal of 31204540 is 4540213.

It is an interprime number because it is at equal distance from previous prime (31204531) and next prime (31204549).

It is a super-2 number, since 2×31204540² = 1947446633223200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31204549) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 780094 + ... + 780133.

It is an arithmetic number, because the mean of its divisors is an integer number (5460798).

Almost surely, 2^31204540 is an apocalyptic number.

It is an amenable number.

31204540 is an abundant number, since it is smaller than the sum of its proper divisors (34325036).

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

31204540 is a wasteful number, since it uses less digits than its factorization.

31204540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1560236 (or 1560234 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 31204540 is about 5586.1023979157. The cubic root of 31204540 is about 314.8274523219.

Adding to 31204540 its reverse (4540213), we get a palindrome (35744753).

The spelling of 31204540 in words is "thirty-one million, two hundred four thousand, five hundred forty".