421684137 has 20 divisors (see below), whose sum is σ = 719913216. Its totient is φ = 240962040.

The previous prime is 421684129. The next prime is 421684171. The reversal of 421684137 is 731486124.

It is not a de Polignac number, because 421684137 - 2³ = 421684129 is a prime.

It is a super-2 number, since 2×421684137² = 355635022794869538, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (421684127) 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 19 ways as a sum of consecutive naturals, for example, 371289 + ... + 372422.

Almost surely, 2^421684137 is an apocalyptic number.

It is an amenable number.

421684137 is a deficient number, since it is larger than the sum of its proper divisors (298229079).

421684137 is an equidigital number, since it uses as much as digits as its factorization.

421684137 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 743730 (or 743721 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 421684137 is about 20534.9491599078. The cubic root of 421684137 is about 749.8868789390.

It can be divided in two parts, 421684 and 137, that added together give a triangular number (421821 = T₉₁₈).

The spelling of 421684137 in words is "four hundred twenty-one million, six hundred eighty-four thousand, one hundred thirty-seven".