43979840 has 28 divisors (see below), whose sum is σ = 104727756. Its totient is φ = 17591808.

The previous prime is 43979779. The next prime is 43979843. The reversal of 43979840 is 4897934.

It can be written as a sum of positive squares in 2 ways, for example, as 28987456 + 14992384 = 5384^2 + 3872^2 .

It is a junction number, because it is equal to n+sod(n) for n = 43979791 and 43979800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43979843) 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, 68399 + ... + 69038.

It is an arithmetic number, because the mean of its divisors is an integer number (3740277).

Almost surely, 2^43979840 is an apocalyptic number.

43979840 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

43979840 is an abundant number, since it is smaller than the sum of its proper divisors (60747916).

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

43979840 is a wasteful number, since it uses less digits than its factorization.

43979840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137454 (or 137444 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 44.

The square root of 43979840 is about 6631.7297894290. The cubic root of 43979840 is about 352.9809072485.

The spelling of 43979840 in words is "forty-three million, nine hundred seventy-nine thousand, eight hundred forty".