252111721 has 2 divisors, whose sum is σ = 252111722. Its totient is φ = 252111720.

The previous prime is 252111697. The next prime is 252111731. The reversal of 252111721 is 127111252.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 244609600 + 7502121 = 15640^2 + 2739^2 .

It is a cyclic number.

It is not a de Polignac number, because 252111721 - 2⁷ = 252111593 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 252111692 and 252111701.

It is not a weakly prime, because it can be changed into another prime (252111731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 126055860 + 126055861.

It is an arithmetic number, because the mean of its divisors is an integer number (126055861).

Almost surely, 2^252111721 is an apocalyptic number.

It is an amenable number.

252111721 is a deficient number, since it is larger than the sum of its proper divisors (1).

252111721 is an equidigital number, since it uses as much as digits as its factorization.

252111721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 280, while the sum is 22.

The square root of 252111721 is about 15878.0263572020. The cubic root of 252111721 is about 631.7292885689.

Adding to 252111721 its reverse (127111252), we get a palindrome (379222973).

The spelling of 252111721 in words is "two hundred fifty-two million, one hundred eleven thousand, seven hundred twenty-one".