16637421 has 8 divisors (see below), whose sum is σ = 22898944. Its totient is φ = 10733760.

The previous prime is 16637371. The next prime is 16637429. The reversal of 16637421 is 12473661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 16637421 - 2⁹ = 16636909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16637429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89356 + ... + 89541.

It is an arithmetic number, because the mean of its divisors is an integer number (2862368).

Almost surely, 2^16637421 is an apocalyptic number.

It is an amenable number.

16637421 is a deficient number, since it is larger than the sum of its proper divisors (6261523).

16637421 is a wasteful number, since it uses less digits than its factorization.

16637421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178931.

The product of its digits is 6048, while the sum is 30.

The square root of 16637421 is about 4078.8994839295. The cubic root of 16637421 is about 255.2869817869.

The spelling of 16637421 in words is "sixteen million, six hundred thirty-seven thousand, four hundred twenty-one".