31345040 has 40 divisors (see below), whose sum is σ = 73120320. Its totient is φ = 12496256.

The previous prime is 31345019. The next prime is 31345049. The reversal of 31345040 is 4054313.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (31345049) 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, 36941 + ... + 37779.

It is an arithmetic number, because the mean of its divisors is an integer number (1828008).

Almost surely, 2^31345040 is an apocalyptic number.

It is an amenable number.

31345040 is an abundant number, since it is smaller than the sum of its proper divisors (41775280).

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

31345040 is a wasteful number, since it uses less digits than its factorization.

31345040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1319 (or 1313 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 31345040 is about 5598.6641263787. The cubic root of 31345040 is about 315.2992537023.

Adding to 31345040 its reverse (4054313), we get a palindrome (35399353).

The spelling of 31345040 in words is "thirty-one million, three hundred forty-five thousand, forty".