1917999394 has 8 divisors (see below), whose sum is σ = 3002086080. Its totient is φ = 917304036.

The previous prime is 1917999331. The next prime is 1917999397. The reversal of 1917999394 is 4939997191.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (1917999397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20847774 + ... + 20847865.

It is an arithmetic number, because the mean of its divisors is an integer number (375260760).

Almost surely, 2^1917999394 is an apocalyptic number.

1917999394 is a deficient number, since it is larger than the sum of its proper divisors (1084086686).

1917999394 is a wasteful number, since it uses less digits than its factorization.

1917999394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41695664.

The product of its digits is 4960116, while the sum is 61.

The square root of 1917999394 is about 43794.9699623142. The cubic root of 1917999394 is about 1242.4611615236.

The spelling of 1917999394 in words is "one billion, nine hundred seventeen million, nine hundred ninety-nine thousand, three hundred ninety-four".