22155987 has 12 divisors (see below), whose sum is σ = 34364616. Its totient is φ = 12660480.

The previous prime is 22155977. The next prime is 22155989. The reversal of 22155987 is 78955122.

It is not a de Polignac number, because 22155987 - 2¹⁰ = 22154963 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22155989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 75214 + ... + 75507.

It is an arithmetic number, because the mean of its divisors is an integer number (2863718).

Almost surely, 2^22155987 is an apocalyptic number.

22155987 is a deficient number, since it is larger than the sum of its proper divisors (12208629).

22155987 is a wasteful number, since it uses less digits than its factorization.

22155987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150738 (or 150731 counting only the distinct ones).

The product of its digits is 50400, while the sum is 39.

The square root of 22155987 is about 4707.0146589957. The cubic root of 22155987 is about 280.8646190397.

The spelling of 22155987 in words is "twenty-two million, one hundred fifty-five thousand, nine hundred eighty-seven".