1891215608493 has 16 divisors (see below), whose sum is σ = 2539881344000. Its totient is φ = 1251680992560.

The previous prime is 1891215608489. The next prime is 1891215608573. The reversal of 1891215608493 is 3948065121981.

It is a happy number.

It is not a de Polignac number, because 1891215608493 - 2² = 1891215608489 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 (1891215608453) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9901308 + ... + 10090506.

It is an arithmetic number, because the mean of its divisors is an integer number (158742584000).

Almost surely, 2^{1891215608493} is an apocalyptic number.

It is an amenable number.

1891215608493 is a deficient number, since it is larger than the sum of its proper divisors (648665735507).

1891215608493 is a wasteful number, since it uses less digits than its factorization.

1891215608493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213312.

The product of its (nonzero) digits is 3732480, while the sum is 57.

The spelling of 1891215608493 in words is "one trillion, eight hundred ninety-one billion, two hundred fifteen million, six hundred eight thousand, four hundred ninety-three".