22251551 has 4 divisors (see below), whose sum is σ = 25430352. Its totient is φ = 19072752.

The previous prime is 22251533. The next prime is 22251569. The reversal of 22251551 is 15515222.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15515222 = 2 ⋅7757611.

It is an interprime number because it is at equal distance from previous prime (22251533) and next prime (22251569).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22251551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22251751) 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, 1589390 + ... + 1589403.

It is an arithmetic number, because the mean of its divisors is an integer number (6357588).

Almost surely, 2^22251551 is an apocalyptic number.

22251551 is a deficient number, since it is larger than the sum of its proper divisors (3178801).

22251551 is an equidigital number, since it uses as much as digits as its factorization.

22251551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3178800.

The product of its digits is 1000, while the sum is 23.

The square root of 22251551 is about 4717.1549688345. The cubic root of 22251551 is about 281.2678516406.

Adding to 22251551 its reverse (15515222), we get a palindrome (37766773).

The spelling of 22251551 in words is "twenty-two million, two hundred fifty-one thousand, five hundred fifty-one".