21142374 has 16 divisors (see below), whose sum is σ = 46128960. Its totient is φ = 6406760.

The previous prime is 21142361. The next prime is 21142379. The reversal of 21142374 is 47324112.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21142379) 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, 160104 + ... + 160235.

It is an arithmetic number, because the mean of its divisors is an integer number (2883060).

Almost surely, 2^21142374 is an apocalyptic number.

21142374 is an abundant number, since it is smaller than the sum of its proper divisors (24986586).

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

21142374 is a wasteful number, since it uses less digits than its factorization.

21142374 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320355.

The product of its digits is 1344, while the sum is 24.

The square root of 21142374 is about 4598.0837312950. The cubic root of 21142374 is about 276.5145044804.

Adding to 21142374 its reverse (47324112), we get a palindrome (68466486).

The spelling of 21142374 in words is "twenty-one million, one hundred forty-two thousand, three hundred seventy-four".