40217861 has 4 divisors (see below), whose sum is σ = 40245792. Its totient is φ = 40189932.

The previous prime is 40217833. The next prime is 40217909. The reversal of 40217861 is 16871204.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40217861 - 2⁶ = 40217797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40217161) 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, 11681 + ... + 14726.

It is an arithmetic number, because the mean of its divisors is an integer number (10061448).

Almost surely, 2^40217861 is an apocalyptic number.

It is an amenable number.

40217861 is a deficient number, since it is larger than the sum of its proper divisors (27931).

40217861 is a wasteful number, since it uses less digits than its factorization.

40217861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27930.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 40217861 is about 6341.7553563662. The cubic root of 40217861 is about 342.6149606098.

The spelling of 40217861 in words is "forty million, two hundred seventeen thousand, eight hundred sixty-one".