43672381 has 4 divisors (see below), whose sum is σ = 43691292. Its totient is φ = 43653472.

The previous prime is 43672373. The next prime is 43672403. The reversal of 43672381 is 18327634.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 26936100 + 16736281 = 5190^2 + 4091^2 .

It is a cyclic number.

It is not a de Polignac number, because 43672381 - 2³ = 43672373 is a prime.

It is a super-2 number, since 2×43672381² = 3814553724418322, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43672351) 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, 5416 + ... + 10801.

It is an arithmetic number, because the mean of its divisors is an integer number (10922823).

Almost surely, 2^43672381 is an apocalyptic number.

It is an amenable number.

43672381 is a deficient number, since it is larger than the sum of its proper divisors (18911).

43672381 is a wasteful number, since it uses less digits than its factorization.

43672381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18910.

The product of its digits is 24192, while the sum is 34.

The square root of 43672381 is about 6608.5082280345. The cubic root of 43672381 is about 352.1564306648.

The spelling of 43672381 in words is "forty-three million, six hundred seventy-two thousand, three hundred eighty-one".