16649139438 has 32 divisors (see below), whose sum is σ = 37343877120. Its totient is φ = 5497844760.

The previous prime is 16649139433. The next prime is 16649139449. The reversal of 16649139438 is 83493194661.

16649139438 is a `hidden beast` number, since 1 + 66 + 491 + 3 + 94 + 3 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16649139433) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1434958 + ... + 1446513.

It is an arithmetic number, because the mean of its divisors is an integer number (1166996160).

Almost surely, 2^16649139438 is an apocalyptic number.

16649139438 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

16649139438 is an abundant number, since it is smaller than the sum of its proper divisors (20694737682).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16649139438 is a wasteful number, since it uses less digits than its factorization.

16649139438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2881589 (or 2881583 counting only the distinct ones).

The product of its digits is 3359232, while the sum is 54.

The spelling of 16649139438 in words is "sixteen billion, six hundred forty-nine million, one hundred thirty-nine thousand, four hundred thirty-eight".