21122143 has 24 divisors (see below), whose sum is σ = 26259552. Its totient is φ = 16633344.

The previous prime is 21122111. The next prime is 21122161. The reversal of 21122143 is 34122112.

It is not a de Polignac number, because 21122143 - 2⁵ = 21122111 is a prime.

It is a super-2 number, since 2×21122143² = 892289849824898, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122183) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 107121 + ... + 107317.

It is an arithmetic number, because the mean of its divisors is an integer number (1094148).

Almost surely, 2^21122143 is an apocalyptic number.

21122143 is a deficient number, since it is larger than the sum of its proper divisors (5137409).

21122143 is a wasteful number, since it uses less digits than its factorization.

21122143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291 (or 274 counting only the distinct ones).

The product of its digits is 96, while the sum is 16.

The square root of 21122143 is about 4595.8832665767. The cubic root of 21122143 is about 276.4262780238.

Adding to 21122143 its reverse (34122112), we get a palindrome (55244255).

The spelling of 21122143 in words is "twenty-one million, one hundred twenty-two thousand, one hundred forty-three".