11951997 has 4 divisors (see below), whose sum is σ = 15936000. Its totient is φ = 7967996.

The previous prime is 11951993. The next prime is 11952001. The reversal of 11951997 is 79915911.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 79915911 = 3 ⋅26638637.

It is an interprime number because it is at equal distance from previous prime (11951993) and next prime (11952001).

It is a cyclic number.

It is not a de Polignac number, because 11951997 - 2² = 11951993 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11951993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1991997 + ... + 1992002.

It is an arithmetic number, because the mean of its divisors is an integer number (3984000).

Almost surely, 2^11951997 is an apocalyptic number.

It is an amenable number.

11951997 is a deficient number, since it is larger than the sum of its proper divisors (3984003).

11951997 is an equidigital number, since it uses as much as digits as its factorization.

11951997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3984002.

The product of its digits is 25515, while the sum is 42.

The square root of 11951997 is about 3457.1660359317. The cubic root of 11951997 is about 228.6371643333.

The spelling of 11951997 in words is "eleven million, nine hundred fifty-one thousand, nine hundred ninety-seven".