31523421 has 8 divisors (see below), whose sum is σ = 42283584. Its totient is φ = 20889440.

The previous prime is 31523419. The next prime is 31523441. The reversal of 31523421 is 12432513.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31523421 - 2¹ = 31523419 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31523411) 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, 30960 + ... + 31961.

It is an arithmetic number, because the mean of its divisors is an integer number (5285448).

Almost surely, 2^31523421 is an apocalyptic number.

It is an amenable number.

31523421 is a deficient number, since it is larger than the sum of its proper divisors (10760163).

31523421 is a wasteful number, since it uses less digits than its factorization.

31523421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63091.

The product of its digits is 720, while the sum is 21.

The square root of 31523421 is about 5614.5722009785. The cubic root of 31523421 is about 315.8962332208.

Adding to 31523421 its reverse (12432513), we get a palindrome (43955934).

The spelling of 31523421 in words is "thirty-one million, five hundred twenty-three thousand, four hundred twenty-one".