11997025421 has 2 divisors, whose sum is σ = 11997025422. Its totient is φ = 11997025420.

The previous prime is 11997025393. The next prime is 11997025483. The reversal of 11997025421 is 12452079911.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7224150025 + 4772875396 = 84995^2 + 69086^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11997025421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11997025121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5998512710 + 5998512711.

It is an arithmetic number, because the mean of its divisors is an integer number (5998512711).

Almost surely, 2^11997025421 is an apocalyptic number.

It is an amenable number.

11997025421 is a deficient number, since it is larger than the sum of its proper divisors (1).

11997025421 is an equidigital number, since it uses as much as digits as its factorization.

11997025421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45360, while the sum is 41.

The spelling of 11997025421 in words is "eleven billion, nine hundred ninety-seven million, twenty-five thousand, four hundred twenty-one".