22405991 has 2 divisors, whose sum is σ = 22405992. Its totient is φ = 22405990.

The previous prime is 22405973. The next prime is 22405993. The reversal of 22405991 is 19950422.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 22405991 - 2⁶ = 22405927 is a prime.

It is a super-3 number, since 3×22405991³ (a number of 23 digits) contains 333 as substring.

Together with 22405993, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22405993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11202995 + 11202996.

It is an arithmetic number, because the mean of its divisors is an integer number (11202996).

Almost surely, 2^22405991 is an apocalyptic number.

22405991 is a deficient number, since it is larger than the sum of its proper divisors (1).

22405991 is an equidigital number, since it uses as much as digits as its factorization.

22405991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 22405991 is about 4733.4966990587. The cubic root of 22405991 is about 281.9170782131.

The spelling of 22405991 in words is "twenty-two million, four hundred five thousand, nine hundred ninety-one".