1673921491 has 16 divisors (see below), whose sum is σ = 1843890048. Its totient is φ = 1506988800.

The previous prime is 1673921479. The next prime is 1673921521. The reversal of 1673921491 is 1941293761.

It is a cyclic number.

It is not a de Polignac number, because 1673921491 - 2²¹ = 1671824339 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1673921891) 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, 548931 + ... + 551971.

It is an arithmetic number, because the mean of its divisors is an integer number (115243128).

Almost surely, 2^1673921491 is an apocalyptic number.

1673921491 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1673921491 is a deficient number, since it is larger than the sum of its proper divisors (169968557).

1673921491 is a wasteful number, since it uses less digits than its factorization.

1673921491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3522.

The product of its digits is 81648, while the sum is 43.

The square root of 1673921491 is about 40913.5856531788. The cubic root of 1673921491 is about 1187.3489204806.

The spelling of 1673921491 in words is "one billion, six hundred seventy-three million, nine hundred twenty-one thousand, four hundred ninety-one".