22155551 has 4 divisors (see below), whose sum is σ = 24169704. Its totient is φ = 20141400.

The previous prime is 22155547. The next prime is 22155559. The reversal of 22155551 is 15555122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 22155551 - 2² = 22155547 is a prime.

It is a super-2 number, since 2×22155551² = 981736880227202, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 22155551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22155559) 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 3 ways as a sum of consecutive naturals, for example, 1007060 + ... + 1007081.

It is an arithmetic number, because the mean of its divisors is an integer number (6042426).

Almost surely, 2^22155551 is an apocalyptic number.

22155551 is a deficient number, since it is larger than the sum of its proper divisors (2014153).

22155551 is a wasteful number, since it uses less digits than its factorization.

22155551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2014152.

The product of its digits is 2500, while the sum is 26.

The square root of 22155551 is about 4706.9683449116. The cubic root of 22155551 is about 280.8627766817.

The spelling of 22155551 in words is "twenty-two million, one hundred fifty-five thousand, five hundred fifty-one".