22978561 has 4 divisors (see below), whose sum is σ = 22988224. Its totient is φ = 22968900.

The previous prime is 22978559. The next prime is 22978567. The reversal of 22978561 is 16587922.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 22978561 - 2¹ = 22978559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22978567) 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, 1516 + ... + 6946.

It is an arithmetic number, because the mean of its divisors is an integer number (5747056).

It is a Proth number, since it is equal to 2805 ⋅ 2¹³ + 1 and 2805 < 2¹³.

Almost surely, 2^22978561 is an apocalyptic number.

It is an amenable number.

22978561 is a deficient number, since it is larger than the sum of its proper divisors (9663).

22978561 is an equidigital number, since it uses as much as digits as its factorization.

22978561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9662.

The product of its digits is 60480, while the sum is 40.

The square root of 22978561 is about 4793.5958319408. The cubic root of 22978561 is about 284.2983086839.

The spelling of 22978561 in words is "twenty-two million, nine hundred seventy-eight thousand, five hundred sixty-one".