43629981 has 8 divisors (see below), whose sum is σ = 58216704. Its totient is φ = 29064960.

The previous prime is 43629977. The next prime is 43629991. The reversal of 43629981 is 18992634.

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

It is not a de Polignac number, because 43629981 - 2² = 43629977 is a prime.

It is a super-2 number, since 2×43629981² = 3807150484120722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43629941) 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, 61 + ... + 9341.

It is an arithmetic number, because the mean of its divisors is an integer number (7277088).

Almost surely, 2^43629981 is an apocalyptic number.

It is an amenable number.

43629981 is a deficient number, since it is larger than the sum of its proper divisors (14586723).

43629981 is a wasteful number, since it uses less digits than its factorization.

43629981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10851.

The product of its digits is 93312, while the sum is 42.

The square root of 43629981 is about 6605.2994633097. The cubic root of 43629981 is about 352.0424282750.

The spelling of 43629981 in words is "forty-three million, six hundred twenty-nine thousand, nine hundred eighty-one".