21196261 has 2 divisors, whose sum is σ = 21196262. Its totient is φ = 21196260.

The previous prime is 21196223. The next prime is 21196277. The reversal of 21196261 is 16269112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19633761 + 1562500 = 4431^2 + 1250^2 .

It is a cyclic number.

It is not a de Polignac number, because 21196261 - 2¹¹ = 21194213 is a prime.

It is equal to p_1341568 and since 21196261 and 1341568 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21196211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10598130 + 10598131.

It is an arithmetic number, because the mean of its divisors is an integer number (10598131).

Almost surely, 2^21196261 is an apocalyptic number.

It is an amenable number.

21196261 is a deficient number, since it is larger than the sum of its proper divisors (1).

21196261 is an equidigital number, since it uses as much as digits as its factorization.

21196261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 28.

The square root of 21196261 is about 4603.9397259304. The cubic root of 21196261 is about 276.7492289199.

The spelling of 21196261 in words is "twenty-one million, one hundred ninety-six thousand, two hundred sixty-one".