11900661 has 4 divisors (see below), whose sum is σ = 15867552. Its totient is φ = 7933772.

The previous prime is 11900657. The next prime is 11900671. The reversal of 11900661 is 16600911.

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: 16600911 = 3 ⋅5533637.

It is a cyclic number.

It is not a de Polignac number, because 11900661 - 2² = 11900657 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11900641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1983441 + ... + 1983446.

It is an arithmetic number, because the mean of its divisors is an integer number (3966888).

Almost surely, 2^11900661 is an apocalyptic number.

It is an amenable number.

11900661 is a deficient number, since it is larger than the sum of its proper divisors (3966891).

11900661 is an equidigital number, since it uses as much as digits as its factorization.

11900661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3966890.

The product of its (nonzero) digits is 324, while the sum is 24.

The square root of 11900661 is about 3449.7334679653. The cubic root of 11900661 is about 228.3093484790.

It can be divided in two parts, 11900 and 661, that added together give a triangular number (12561 = T₁₅₈).

The spelling of 11900661 in words is "eleven million, nine hundred thousand, six hundred sixty-one".