31720542 has 48 divisors (see below), whose sum is σ = 77023872. Its totient is φ = 8667120.

The previous prime is 31720517. The next prime is 31720543. The reversal of 31720542 is 24502713.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31720543) 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 23 ways as a sum of consecutive naturals, for example, 4417 + ... + 9107.

It is an arithmetic number, because the mean of its divisors is an integer number (1604664).

Almost surely, 2^31720542 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31720542, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38511936).

31720542 is an abundant number, since it is smaller than the sum of its proper divisors (45303330).

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

31720542 is a wasteful number, since it uses less digits than its factorization.

31720542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4733 (or 4726 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 31720542 is about 5632.0992533868. The cubic root of 31720542 is about 316.5533154171.

The spelling of 31720542 in words is "thirty-one million, seven hundred twenty thousand, five hundred forty-two".