1673653421 has 4 divisors (see below), whose sum is σ = 1825803744. Its totient is φ = 1521503100.

The previous prime is 1673653391. The next prime is 1673653463. The reversal of 1673653421 is 1243563761.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1673653421 - 2⁶ = 1673653357 is a prime.

It is a super-2 number, since 2×1673653421² = 5602231547250006482, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1673653021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 76075145 + ... + 76075166.

It is an arithmetic number, because the mean of its divisors is an integer number (456450936).

Almost surely, 2^1673653421 is an apocalyptic number.

1673653421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1673653421 is a deficient number, since it is larger than the sum of its proper divisors (152150323).

1673653421 is a wasteful number, since it uses less digits than its factorization.

1673653421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152150322.

The product of its digits is 90720, while the sum is 38.

The square root of 1673653421 is about 40910.3094708412. The cubic root of 1673653421 is about 1187.2855344697.

The spelling of 1673653421 in words is "one billion, six hundred seventy-three million, six hundred fifty-three thousand, four hundred twenty-one".