22151281 has 2 divisors, whose sum is σ = 22151282. Its totient is φ = 22151280.

The previous prime is 22151279. The next prime is 22151411. The reversal of 22151281 is 18215122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13395600 + 8755681 = 3660^2 + 2959^2 .

It is a cyclic number.

It is not a de Polignac number, because 22151281 - 2¹ = 22151279 is a prime.

It is a super-2 number, since 2×22151281² = 981358499881922, which contains 22 as substring.

Together with 22151279, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (22151201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11075640 + 11075641.

It is an arithmetic number, because the mean of its divisors is an integer number (11075641).

Almost surely, 2^22151281 is an apocalyptic number.

It is an amenable number.

22151281 is a deficient number, since it is larger than the sum of its proper divisors (1).

22151281 is an equidigital number, since it uses as much as digits as its factorization.

22151281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 320, while the sum is 22.

The square root of 22151281 is about 4706.5147402298. The cubic root of 22151281 is about 280.8447321277.

The spelling of 22151281 in words is "twenty-two million, one hundred fifty-one thousand, two hundred eighty-one".