253668681 has 24 divisors (see below), whose sum is σ = 428972544. Its totient is φ = 141416640.

The previous prime is 253668637. The next prime is 253668719. The reversal of 253668681 is 186866352.

It is not a de Polignac number, because 253668681 - 2⁶ = 253668617 is a prime.

It is a super-2 number, since 2×253668681² = 128695599440559522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (253668281) 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, 46521 + ... + 51686.

It is an arithmetic number, because the mean of its divisors is an integer number (17873856).

Almost surely, 2^253668681 is an apocalyptic number.

253668681 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

253668681 is a deficient number, since it is larger than the sum of its proper divisors (175303863).

253668681 is a wasteful number, since it uses less digits than its factorization.

253668681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98261 (or 98258 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 253668681 is about 15926.9796571729. The cubic root of 253668681 is about 633.0270722083.

It can be divided in two parts, 2536 and 68681, that added together give a palindrome (71217).

The spelling of 253668681 in words is "two hundred fifty-three million, six hundred sixty-eight thousand, six hundred eighty-one".