11897120381 has 2 divisors, whose sum is σ = 11897120382. Its totient is φ = 11897120380.

The previous prime is 11897120377. The next prime is 11897120471. The reversal of 11897120381 is 18302179811.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9227331481 + 2669788900 = 96059^2 + 51670^2 .

It is a cyclic number.

It is not a de Polignac number, because 11897120381 - 2² = 11897120377 is a prime.

It is a super-2 number, since 2×11897120381² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11897120321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5948560190 + 5948560191.

It is an arithmetic number, because the mean of its divisors is an integer number (5948560191).

Almost surely, 2^11897120381 is an apocalyptic number.

It is an amenable number.

11897120381 is a deficient number, since it is larger than the sum of its proper divisors (1).

11897120381 is an equidigital number, since it uses as much as digits as its factorization.

11897120381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24192, while the sum is 41.

The spelling of 11897120381 in words is "eleven billion, eight hundred ninety-seven million, one hundred twenty thousand, three hundred eighty-one".