22742581 has 4 divisors (see below), whose sum is σ = 23016672. Its totient is φ = 22468492.

The previous prime is 22742557. The next prime is 22742611. The reversal of 22742581 is 18524722.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18524722 = 2 ⋅9262361.

It is a cyclic number.

It is not a de Polignac number, because 22742581 - 2⁷ = 22742453 is a prime.

It is a super-2 number, since 2×22742581² = 1034449981083122, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22742381) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136921 + ... + 137086.

It is an arithmetic number, because the mean of its divisors is an integer number (5754168).

Almost surely, 2^22742581 is an apocalyptic number.

It is an amenable number.

22742581 is a deficient number, since it is larger than the sum of its proper divisors (274091).

22742581 is an equidigital number, since it uses as much as digits as its factorization.

22742581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274090.

The product of its digits is 8960, while the sum is 31.

The square root of 22742581 is about 4768.9182211483. The cubic root of 22742581 is about 283.3217506991.

The spelling of 22742581 in words is "twenty-two million, seven hundred forty-two thousand, five hundred eighty-one".