20111222251 has 2 divisors, whose sum is σ = 20111222252. Its totient is φ = 20111222250.

The previous prime is 20111222237. The next prime is 20111222273. The reversal of 20111222251 is 15222211102.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20111222251 is a prime.

It is a super-2 number, since 2×20111222251² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20111220251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10055611125 + 10055611126.

It is an arithmetic number, because the mean of its divisors is an integer number (10055611126).

Almost surely, 2^20111222251 is an apocalyptic number.

20111222251 is a deficient number, since it is larger than the sum of its proper divisors (1).

20111222251 is an equidigital number, since it uses as much as digits as its factorization.

20111222251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 160, while the sum is 19.

Adding to 20111222251 its reverse (15222211102), we get a palindrome (35333433353).

The spelling of 20111222251 in words is "twenty billion, one hundred eleven million, two hundred twenty-two thousand, two hundred fifty-one".