253721656 has 8 divisors (see below), whose sum is σ = 475728120. Its totient is φ = 126860824.

The previous prime is 253721641. The next prime is 253721659. The reversal of 253721656 is 656127352.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (253721659) 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 as a sum of consecutive naturals, namely, 15857596 + ... + 15857611.

It is an arithmetic number, because the mean of its divisors is an integer number (59466015).

Almost surely, 2^253721656 is an apocalyptic number.

It is an amenable number.

253721656 is a deficient number, since it is larger than the sum of its proper divisors (222006464).

253721656 is a wasteful number, since it uses less digits than its factorization.

253721656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31715213 (or 31715209 counting only the distinct ones).

The product of its digits is 75600, while the sum is 37.

The square root of 253721656 is about 15928.6426289248. The cubic root of 253721656 is about 633.0711352947.

It can be divided in two parts, 25372 and 1656, that added together give a triangular number (27028 = T₂₃₂).

The spelling of 253721656 in words is "two hundred fifty-three million, seven hundred twenty-one thousand, six hundred fifty-six".