6440136 has 64 divisors (see below), whose sum is σ = 16873920. Its totient is φ = 2046720.

The previous prime is 6440131. The next prime is 6440141. The reversal of 6440136 is 6310446.

6440136 is nontrivially palindromic in base 13.

It is an interprime number because it is at equal distance from previous prime (6440131) and next prime (6440141).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (6440131) 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, 77551 + ... + 77633.

It is an arithmetic number, because the mean of its divisors is an integer number (263655).

Almost surely, 2^6440136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6440136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8436960).

6440136 is an abundant number, since it is smaller than the sum of its proper divisors (10433784).

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

6440136 is a wasteful number, since it uses less digits than its factorization.

6440136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206 (or 202 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 6440136 is about 2537.7423037022. The cubic root of 6440136 is about 186.0508590254.

The spelling of 6440136 in words is "six million, four hundred forty thousand, one hundred thirty-six".