721523141 has 4 divisors (see below), whose sum is σ = 722341152. Its totient is φ = 720705132.

The previous prime is 721523123. The next prime is 721523147. The reversal of 721523141 is 141325127.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 721523141 - 2¹⁸ = 721260997 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 721523141.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721523147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 407681 + ... + 409446.

It is an arithmetic number, because the mean of its divisors is an integer number (180585288).

Almost surely, 2^721523141 is an apocalyptic number.

It is an amenable number.

721523141 is a deficient number, since it is larger than the sum of its proper divisors (818011).

721523141 is an equidigital number, since it uses as much as digits as its factorization.

721523141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 818010.

The product of its digits is 1680, while the sum is 26.

The square root of 721523141 is about 26861.1827922748. The cubic root of 721523141 is about 896.9125237264.

Adding to 721523141 its reverse (141325127), we get a palindrome (862848268).

The spelling of 721523141 in words is "seven hundred twenty-one million, five hundred twenty-three thousand, one hundred forty-one".