22142781 has 16 divisors (see below), whose sum is σ = 33504000. Its totient is φ = 14446944.

The previous prime is 22142749. The next prime is 22142797. The reversal of 22142781 is 18724122.

It is not a de Polignac number, because 22142781 - 2⁵ = 22142749 is a prime.

It is a super-2 number, since 2×22142781² = 980605500827922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22142881) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7456 + ... + 9993.

It is an arithmetic number, because the mean of its divisors is an integer number (2094000).

Almost surely, 2^22142781 is an apocalyptic number.

It is an amenable number.

22142781 is a deficient number, since it is larger than the sum of its proper divisors (11361219).

22142781 is a wasteful number, since it uses less digits than its factorization.

22142781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17505 (or 17499 counting only the distinct ones).

The product of its digits is 1792, while the sum is 27.

The square root of 22142781 is about 4705.6116499346. The cubic root of 22142781 is about 280.8088051516.

The spelling of 22142781 in words is "twenty-two million, one hundred forty-two thousand, seven hundred eighty-one".