221312051 has 2 divisors, whose sum is σ = 221312052. Its totient is φ = 221312050.

The previous prime is 221312033. The next prime is 221312053. The reversal of 221312051 is 150213122.

It is a happy number.

221312051 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221312051 - 2¹⁴ = 221295667 is a prime.

It is a Sophie Germain prime.

Together with 221312053, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (221312053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110656025 + 110656026.

It is an arithmetic number, because the mean of its divisors is an integer number (110656026).

Almost surely, 2^221312051 is an apocalyptic number.

221312051 is a deficient number, since it is larger than the sum of its proper divisors (1).

221312051 is an equidigital number, since it uses as much as digits as its factorization.

221312051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 221312051 is about 14876.5604559656. The cubic root of 221312051 is about 604.8787872730.

Adding to 221312051 its reverse (150213122), we get a palindrome (371525173).

The spelling of 221312051 in words is "two hundred twenty-one million, three hundred twelve thousand, fifty-one".