23221506 has 32 divisors (see below), whose sum is σ = 57904128. Its totient is φ = 6031440.

The previous prime is 23221487. The next prime is 23221531. The reversal of 23221506 is 60512232.

23221506 = T₂₂₄ + T₂₂₅ + ... + T₅₃₁.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24670 + ... + 25593.

It is an arithmetic number, because the mean of its divisors is an integer number (1809504).

Almost surely, 2^23221506 is an apocalyptic number.

23221506 is an abundant number, since it is smaller than the sum of its proper divisors (34682622).

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

23221506 is a wasteful number, since it uses less digits than its factorization.

23221506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50286.

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 23221506 is about 4818.8697845034. The cubic root of 23221506 is about 285.2967300389.

Adding to 23221506 its reverse (60512232), we get a palindrome (83733738).

It can be divided in two parts, 2322 and 1506, that added together give a triangular number (3828 = T₈₇).

The spelling of 23221506 in words is "twenty-three million, two hundred twenty-one thousand, five hundred six".