1351809121739 has 4 divisors (see below), whose sum is σ = 1355338649856. Its totient is φ = 1348279593624.

The previous prime is 1351809121723. The next prime is 1351809121757. The reversal of 1351809121739 is 9371219081531.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1351809121739 - 2⁴ = 1351809121723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1351809129739) 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, 1764763484 + ... + 1764764249.

It is an arithmetic number, because the mean of its divisors is an integer number (338834662464).

Almost surely, 2^{1351809121739} is an apocalyptic number.

1351809121739 is a deficient number, since it is larger than the sum of its proper divisors (3529528117).

1351809121739 is an equidigital number, since it uses as much as digits as its factorization.

1351809121739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3529528116.

The product of its (nonzero) digits is 408240, while the sum is 50.

The spelling of 1351809121739 in words is "one trillion, three hundred fifty-one billion, eight hundred nine million, one hundred twenty-one thousand, seven hundred thirty-nine".