249749397 has 24 divisors (see below), whose sum is σ = 386282520. Its totient is φ = 154936320.

The previous prime is 249749389. The next prime is 249749413. The reversal of 249749397 is 793947942.

It is a happy number.

249749397 is a `hidden beast` number, since 249 + 7 + 4 + 9 + 397 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 5171076 + 244578321 = 2274^2 + 15639^2 .

It is not a de Polignac number, because 249749397 - 2³ = 249749389 is a prime.

It is a super-2 number, since 2×249749397² = 124749522603727218, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (249749317) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4447 + ... + 22787.

It is an arithmetic number, because the mean of its divisors is an integer number (16095105).

Almost surely, 2^249749397 is an apocalyptic number.

It is an amenable number.

249749397 is a deficient number, since it is larger than the sum of its proper divisors (136533123).

249749397 is a wasteful number, since it uses less digits than its factorization.

249749397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18453 (or 18450 counting only the distinct ones).

The product of its digits is 3429216, while the sum is 54.

The square root of 249749397 is about 15803.4615511919. The cubic root of 249749397 is about 629.7499612447.

The spelling of 249749397 in words is "two hundred forty-nine million, seven hundred forty-nine thousand, three hundred ninety-seven".