1921791427 has 8 divisors (see below), whose sum is σ = 2005791264. Its totient is φ = 1837828608.

The previous prime is 1921791419. The next prime is 1921791437. The reversal of 1921791427 is 7241971291.

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

It is a cyclic number.

It is not a de Polignac number, because 1921791427 - 2³ = 1921791419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1921791437) 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, 175773 + ... + 186385.

It is an arithmetic number, because the mean of its divisors is an integer number (250723908).

Almost surely, 2^1921791427 is an apocalyptic number.

1921791427 is a deficient number, since it is larger than the sum of its proper divisors (83999837).

1921791427 is a wasteful number, since it uses less digits than its factorization.

1921791427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18509.

The product of its digits is 63504, while the sum is 43.

The square root of 1921791427 is about 43838.2416047907. The cubic root of 1921791427 is about 1243.2794364020.

The spelling of 1921791427 in words is "one billion, nine hundred twenty-one million, seven hundred ninety-one thousand, four hundred twenty-seven".