1721145413 has 4 divisors (see below), whose sum is σ = 1853541228. Its totient is φ = 1588749600.

The previous prime is 1721145409. The next prime is 1721145421. The reversal of 1721145413 is 3145411271.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1073086564 + 648058849 = 32758^2 + 25457^2 .

It is a cyclic number.

It is not a de Polignac number, because 1721145413 - 2² = 1721145409 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1721145473) 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, 66197888 + ... + 66197913.

It is an arithmetic number, because the mean of its divisors is an integer number (463385307).

Almost surely, 2^1721145413 is an apocalyptic number.

1721145413 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1721145413 is a deficient number, since it is larger than the sum of its proper divisors (132395815).

1721145413 is a wasteful number, since it uses less digits than its factorization.

1721145413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132395814.

The product of its digits is 3360, while the sum is 29.

The square root of 1721145413 is about 41486.6895883487. The cubic root of 1721145413 is about 1198.4111873701.

Adding to 1721145413 its reverse (3145411271), we get a palindrome (4866556684).

The spelling of 1721145413 in words is "one billion, seven hundred twenty-one million, one hundred forty-five thousand, four hundred thirteen".