250191661 has 4 divisors (see below), whose sum is σ = 250338592. Its totient is φ = 250044732.

The previous prime is 250191619. The next prime is 250191691. The reversal of 250191661 is 166191052.

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.

It is a cyclic number.

It is not a de Polignac number, because 250191661 - 2²⁷ = 115973933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (250191611) 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, 70881 + ... + 74326.

It is an arithmetic number, because the mean of its divisors is an integer number (62584648).

Almost surely, 2^250191661 is an apocalyptic number.

It is an amenable number.

250191661 is a deficient number, since it is larger than the sum of its proper divisors (146931).

250191661 is a wasteful number, since it uses less digits than its factorization.

250191661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146930.

The product of its (nonzero) digits is 3240, while the sum is 31.

The square root of 250191661 is about 15817.4479926441. The cubic root of 250191661 is about 630.1214689777.

The spelling of 250191661 in words is "two hundred fifty million, one hundred ninety-one thousand, six hundred sixty-one".