153013721 has 6 divisors (see below), whose sum is σ = 177995610. Its totient is φ = 131154576.

The previous prime is 153013711. The next prime is 153013723. The reversal of 153013721 is 127310351.

It can be written as a sum of positive squares in only one way, i.e., 118026496 + 34987225 = 10864^2 + 5915^2 .

It is a de Polignac number, because none of the positive numbers 2^k-153013721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (153013723) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1561316 + ... + 1561413.

It is an arithmetic number, because the mean of its divisors is an integer number (29665935).

Almost surely, 2^153013721 is an apocalyptic number.

It is an amenable number.

153013721 is a deficient number, since it is larger than the sum of its proper divisors (24981889).

153013721 is an equidigital number, since it uses as much as digits as its factorization.

153013721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3122743 (or 3122736 counting only the distinct ones).

The product of its (nonzero) digits is 630, while the sum is 23.

The square root of 153013721 is about 12369.8715029704. The cubic root of 153013721 is about 534.8641119927.

It can be divided in two parts, 1530 and 13721, that added together give a palindrome (15251).

The spelling of 153013721 in words is "one hundred fifty-three million, thirteen thousand, seven hundred twenty-one".