21234100961 has 2 divisors, whose sum is σ = 21234100962. Its totient is φ = 21234100960.

The previous prime is 21234100931. The next prime is 21234101017. The reversal of 21234100961 is 16900143212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15882300625 + 5351800336 = 126025^2 + 73156^2 .

It is a cyclic number.

It is not a de Polignac number, because 21234100961 - 2⁶ = 21234100897 is a prime.

It is a super-2 number, since 2×21234100961² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21234100931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10617050480 + 10617050481.

It is an arithmetic number, because the mean of its divisors is an integer number (10617050481).

Almost surely, 2^21234100961 is an apocalyptic number.

It is an amenable number.

21234100961 is a deficient number, since it is larger than the sum of its proper divisors (1).

21234100961 is an equidigital number, since it uses as much as digits as its factorization.

21234100961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 29.

The spelling of 21234100961 in words is "twenty-one billion, two hundred thirty-four million, one hundred thousand, nine hundred sixty-one".