21122142 has 16 divisors (see below), whose sum is σ = 44081280. Its totient is φ = 6734552.

The previous prime is 21122111. The next prime is 21122161. The reversal of 21122142 is 24122112.

It is a super-2 number, since 2×21122142² = 892289765336328, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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, 76392 + ... + 76667.

It is an arithmetic number, because the mean of its divisors is an integer number (2755080).

Almost surely, 2^21122142 is an apocalyptic number.

21122142 is an abundant number, since it is smaller than the sum of its proper divisors (22959138).

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

21122142 is a wasteful number, since it uses less digits than its factorization.

21122142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153087.

The product of its digits is 64, while the sum is 15.

The square root of 21122142 is about 4595.8831577837. The cubic root of 21122142 is about 276.4262736614.

Adding to 21122142 its reverse (24122112), we get a palindrome (45244254).

The spelling of 21122142 in words is "twenty-one million, one hundred twenty-two thousand, one hundred forty-two".