421681994 has 16 divisors (see below), whose sum is σ = 648193920. Its totient is φ = 205632000.

The previous prime is 421681961. The next prime is 421682039. The reversal of 421681994 is 499186124.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 61322 + ... + 67850.

It is an arithmetic number, because the mean of its divisors is an integer number (40512120).

Almost surely, 2^421681994 is an apocalyptic number.

421681994 is a deficient number, since it is larger than the sum of its proper divisors (226511926).

421681994 is a wasteful number, since it uses less digits than its factorization.

421681994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7325.

The product of its digits is 124416, while the sum is 44.

The square root of 421681994 is about 20534.8969805061. The cubic root of 421681994 is about 749.8856086278.

The spelling of 421681994 in words is "four hundred twenty-one million, six hundred eighty-one thousand, nine hundred ninety-four".