253749921 has 16 divisors (see below), whose sum is σ = 358713600. Its totient is φ = 159105168.

The previous prime is 253749917. The next prime is 253749931. The reversal of 253749921 is 129947352.

It is not a de Polignac number, because 253749921 - 2² = 253749917 is a prime.

It is not an unprimeable number, because it can be changed into a prime (253749901) 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 15 ways as a sum of consecutive naturals, for example, 8091 + ... + 23936.

It is an arithmetic number, because the mean of its divisors is an integer number (22419600).

Almost surely, 2^253749921 is an apocalyptic number.

It is an amenable number.

253749921 is a deficient number, since it is larger than the sum of its proper divisors (104963679).

253749921 is a wasteful number, since it uses less digits than its factorization.

253749921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32188.

The product of its digits is 136080, while the sum is 42.

The square root of 253749921 is about 15929.5298424028. The cubic root of 253749921 is about 633.0946428022.

The spelling of 253749921 in words is "two hundred fifty-three million, seven hundred forty-nine thousand, nine hundred twenty-one".