1641723281813 has 4 divisors (see below), whose sum is σ = 1642830311808. Its totient is φ = 1640616251820.

The previous prime is 1641723281797. The next prime is 1641723281837. The reversal of 1641723281813 is 3181823271461.

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 1641723281813 - 2⁴ = 1641723281797 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 (1641723281873) 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, 553512773 + ... + 553515738.

It is an arithmetic number, because the mean of its divisors is an integer number (410707577952).

Almost surely, 2^{1641723281813} is an apocalyptic number.

It is an amenable number.

1641723281813 is a deficient number, since it is larger than the sum of its proper divisors (1107029995).

1641723281813 is a wasteful number, since it uses less digits than its factorization.

1641723281813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1107029994.

The product of its digits is 387072, while the sum is 47.

The spelling of 1641723281813 in words is "one trillion, six hundred forty-one billion, seven hundred twenty-three million, two hundred eighty-one thousand, eight hundred thirteen".