40006891 has 8 divisors (see below), whose sum is σ = 40869360. Its totient is φ = 39148512.

The previous prime is 40006871. The next prime is 40006903. The reversal of 40006891 is 19860004.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40006891 is a prime.

It is not an unprimeable number, because it can be changed into a prime (40006871) 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, 26236 + ... + 27718.

It is an arithmetic number, because the mean of its divisors is an integer number (5108670).

Almost surely, 2^40006891 is an apocalyptic number.

40006891 is a deficient number, since it is larger than the sum of its proper divisors (862469).

40006891 is a wasteful number, since it uses less digits than its factorization.

40006891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2045.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 40006891 is about 6325.1000782596. The cubic root of 40006891 is about 342.0148272814.

Adding to 40006891 its reverse (19860004), we get a palindrome (59866895).

The spelling of 40006891 in words is "forty million, six thousand, eight hundred ninety-one".