253721261 has 8 divisors (see below), whose sum is σ = 262899000. Its totient is φ = 244572160.

The previous prime is 253721249. The next prime is 253721297. The reversal of 253721261 is 162127352.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 40386025 + 213335236 = 6355^2 + 14606^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-253721261 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (253721201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11765 + ... + 25413.

It is an arithmetic number, because the mean of its divisors is an integer number (32862375).

Almost surely, 2^253721261 is an apocalyptic number.

253721261 is the 7124-th centered decagonal number.

It is an amenable number.

253721261 is a deficient number, since it is larger than the sum of its proper divisors (9177739).

253721261 is a wasteful number, since it uses less digits than its factorization.

253721261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14319.

The product of its digits is 5040, while the sum is 29.

The square root of 253721261 is about 15928.6302298722. The cubic root of 253721261 is about 633.0708067677.

The spelling of 253721261 in words is "two hundred fifty-three million, seven hundred twenty-one thousand, two hundred sixty-one".