16438631 has 4 divisors (see below), whose sum is σ = 17933064. Its totient is φ = 14944200.

The previous prime is 16438607. The next prime is 16438637. The reversal of 16438631 is 13683461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13683461 = 11 ⋅1243951.

It is a cyclic number.

It is not a de Polignac number, because 16438631 - 2¹⁰ = 16437607 is a prime.

It is a super-2 number, since 2×16438631² = 540457178308322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16438637) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 747200 + ... + 747221.

It is an arithmetic number, because the mean of its divisors is an integer number (4483266).

Almost surely, 2^16438631 is an apocalyptic number.

16438631 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

16438631 is a deficient number, since it is larger than the sum of its proper divisors (1494433).

16438631 is a wasteful number, since it uses less digits than its factorization.

16438631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1494432.

The product of its digits is 10368, while the sum is 32.

The square root of 16438631 is about 4054.4581635528. The cubic root of 16438631 is about 254.2661510521.

The spelling of 16438631 in words is "sixteen million, four hundred thirty-eight thousand, six hundred thirty-one".