671231421 has 16 divisors (see below), whose sum is σ = 1136476800. Its totient is φ = 383560704.

The previous prime is 671231399. The next prime is 671231443. The reversal of 671231421 is 124132176.

671231421 is a `hidden beast` number, since 6 + 7 + 1 + 231 + 421 = 666.

It is an interprime number because it is at equal distance from previous prime (671231399) and next prime (671231443).

It is not a de Polignac number, because 671231421 - 2⁵ = 671231389 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (671231461) 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 15 ways as a sum of consecutive naturals, for example, 1775556 + ... + 1775933.

It is an arithmetic number, because the mean of its divisors is an integer number (71029800).

Almost surely, 2^671231421 is an apocalyptic number.

It is an amenable number.

671231421 is a deficient number, since it is larger than the sum of its proper divisors (465245379).

671231421 is a wasteful number, since it uses less digits than its factorization.

671231421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3551505 (or 3551499 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 671231421 is about 25908.1342632000. The cubic root of 671231421 is about 875.5697713792.

Adding to 671231421 its reverse (124132176), we get a palindrome (795363597).

The spelling of 671231421 in words is "six hundred seventy-one million, two hundred thirty-one thousand, four hundred twenty-one".