43664690 has 8 divisors (see below), whose sum is σ = 78596460. Its totient is φ = 17465872.

The previous prime is 43664689. The next prime is 43664693. The reversal of 43664690 is 9646634.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 42601729 + 1062961 = 6527^2 + 1031^2 .

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

It is a super-2 number, since 2×43664690² = 3813210305592200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (43664693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2183225 + ... + 2183244.

Almost surely, 2^43664690 is an apocalyptic number.

43664690 is a deficient number, since it is larger than the sum of its proper divisors (34931770).

43664690 is a wasteful number, since it uses less digits than its factorization.

43664690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4366476.

The product of its (nonzero) digits is 93312, while the sum is 38.

The square root of 43664690 is about 6607.9263010418. The cubic root of 43664690 is about 352.1357570792.

The spelling of 43664690 in words is "forty-three million, six hundred sixty-four thousand, six hundred ninety".