31425540 has 24 divisors (see below), whose sum is σ = 87991680. Its totient is φ = 8380128.

The previous prime is 31425539. The next prime is 31425547. The reversal of 31425540 is 4552413.

It is a self number, because there is not a number n which added to its sum of digits gives 31425540.

It is not an unprimeable number, because it can be changed into a prime (31425547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 261820 + ... + 261939.

It is an arithmetic number, because the mean of its divisors is an integer number (3666320).

Almost surely, 2^31425540 is an apocalyptic number.

31425540 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31425540 is an abundant number, since it is smaller than the sum of its proper divisors (56566140).

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

31425540 is a wasteful number, since it uses less digits than its factorization.

31425540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 523771 (or 523769 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 31425540 is about 5605.8487314590. The cubic root of 31425540 is about 315.5689390350.

Adding to 31425540 its reverse (4552413), we get a palindrome (35977953).

The spelling of 31425540 in words is "thirty-one million, four hundred twenty-five thousand, five hundred forty".