1872197813 has 4 divisors (see below), whose sum is σ = 1970734560. Its totient is φ = 1773661068.

The previous prime is 1872197797. The next prime is 1872197819. The reversal of 1872197813 is 3187912781.

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 1872197813 - 2⁴ = 1872197797 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 (1872197819) 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, 49268345 + ... + 49268382.

It is an arithmetic number, because the mean of its divisors is an integer number (492683640).

Almost surely, 2^1872197813 is an apocalyptic number.

It is an amenable number.

1872197813 is a deficient number, since it is larger than the sum of its proper divisors (98536747).

1872197813 is an equidigital number, since it uses as much as digits as its factorization.

1872197813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98536746.

The product of its digits is 169344, while the sum is 47.

The square root of 1872197813 is about 43268.9012224716. The cubic root of 1872197813 is about 1232.4914386765.

The spelling of 1872197813 in words is "one billion, eight hundred seventy-two million, one hundred ninety-seven thousand, eight hundred thirteen".