249779987 has 8 divisors (see below), whose sum is σ = 258603840. Its totient is φ = 240970240.

The previous prime is 249779983. The next prime is 249779993. The reversal of 249779987 is 789977942.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 249779987 - 2² = 249779983 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (249779983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43187 + ... + 48627.

It is an arithmetic number, because the mean of its divisors is an integer number (32325480).

Almost surely, 2^249779987 is an apocalyptic number.

249779987 is a deficient number, since it is larger than the sum of its proper divisors (8823853).

249779987 is a wasteful number, since it uses less digits than its factorization.

249779987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7053.

The product of its digits is 16003008, while the sum is 62.

The square root of 249779987 is about 15804.4293474962. The cubic root of 249779987 is about 629.7756713699.

The spelling of 249779987 in words is "two hundred forty-nine million, seven hundred seventy-nine thousand, nine hundred eighty-seven".