221098961 has 2 divisors, whose sum is σ = 221098962. Its totient is φ = 221098960.

The previous prime is 221098883. The next prime is 221098967. The reversal of 221098961 is 169890122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 193210000 + 27888961 = 13900^2 + 5281^2 .

It is a cyclic number.

It is not a de Polignac number, because 221098961 - 2¹⁴ = 221082577 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (221098967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110549480 + 110549481.

It is an arithmetic number, because the mean of its divisors is an integer number (110549481).

Almost surely, 2^221098961 is an apocalyptic number.

It is an amenable number.

221098961 is a deficient number, since it is larger than the sum of its proper divisors (1).

221098961 is an equidigital number, since it uses as much as digits as its factorization.

221098961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 221098961 is about 14869.3967934143. The cubic root of 221098961 is about 604.6845893661.

It can be divided in two parts, 22 and 1098961, that multiplied together give a palindrome (24177142).

The spelling of 221098961 in words is "two hundred twenty-one million, ninety-eight thousand, nine hundred sixty-one".