1921136913 has 8 divisors (see below), whose sum is σ = 2846128800. Its totient is φ = 1280757924.

The previous prime is 1921136897. The next prime is 1921136927. The reversal of 1921136913 is 3196311291.

It is not a de Polignac number, because 1921136913 - 2⁴ = 1921136897 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1921136933) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35576583 + ... + 35576636.

It is an arithmetic number, because the mean of its divisors is an integer number (355766100).

Almost surely, 2^1921136913 is an apocalyptic number.

It is an amenable number.

1921136913 is a deficient number, since it is larger than the sum of its proper divisors (924991887).

1921136913 is an equidigital number, since it uses as much as digits as its factorization.

1921136913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71153228 (or 71153222 counting only the distinct ones).

The product of its digits is 8748, while the sum is 36.

The square root of 1921136913 is about 43830.7758658229. The cubic root of 1921136913 is about 1243.1382771025.

The spelling of 1921136913 in words is "one billion, nine hundred twenty-one million, one hundred thirty-six thousand, nine hundred thirteen".