16387645 has 8 divisors (see below), whose sum is σ = 19688760. Its totient is φ = 13094400.

The previous prime is 16387627. The next prime is 16387649. The reversal of 16387645 is 54678361.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 974169 + 15413476 = 987^2 + 3926^2 .

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

It is not a de Polignac number, because 16387645 - 2⁷ = 16387517 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16387598 and 16387607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16387649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4641 + ... + 7369.

It is an arithmetic number, because the mean of its divisors is an integer number (2461095).

Almost surely, 2^16387645 is an apocalyptic number.

It is an amenable number.

16387645 is a deficient number, since it is larger than the sum of its proper divisors (3301115).

16387645 is a wasteful number, since it uses less digits than its factorization.

16387645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3935.

The product of its digits is 120960, while the sum is 40.

The square root of 16387645 is about 4048.1656339631. The cubic root of 16387645 is about 254.0030018039.

It can be divided in two parts, 1638 and 7645, that multiplied together give a triangular number (12522510 = T₅₀₀₄).

The spelling of 16387645 in words is "sixteen million, three hundred eighty-seven thousand, six hundred forty-five".