40643647 has 4 divisors (see below), whose sum is σ = 44338536. Its totient is φ = 36948760.

The previous prime is 40643639. The next prime is 40643663. The reversal of 40643647 is 74634604.

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

It is a cyclic number.

It is not a de Polignac number, because 40643647 - 2³ = 40643639 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40643347) 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, 1847428 + ... + 1847449.

It is an arithmetic number, because the mean of its divisors is an integer number (11084634).

Almost surely, 2^40643647 is an apocalyptic number.

40643647 is a deficient number, since it is larger than the sum of its proper divisors (3694889).

40643647 is a wasteful number, since it uses less digits than its factorization.

40643647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3694888.

The product of its (nonzero) digits is 48384, while the sum is 34.

The square root of 40643647 is about 6375.2370152019. The cubic root of 40643647 is about 343.8198054600.

The spelling of 40643647 in words is "forty million, six hundred forty-three thousand, six hundred forty-seven".