40206691 has 16 divisors (see below), whose sum is σ = 49125888. Its totient is φ = 32155200.

The previous prime is 40206653. The next prime is 40206707. The reversal of 40206691 is 19660204.

It is a de Polignac number, because none of the positive numbers 2^k-40206691 is a prime.

It is not an unprimeable number, because it can be changed into a prime (40206631) 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 15 ways as a sum of consecutive naturals, for example, 3556 + ... + 9646.

It is an arithmetic number, because the mean of its divisors is an integer number (3070368).

Almost surely, 2^40206691 is an apocalyptic number.

40206691 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

40206691 is a deficient number, since it is larger than the sum of its proper divisors (8919197).

40206691 is a wasteful number, since it uses less digits than its factorization.

40206691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6162.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 40206691 is about 6340.8746242139. The cubic root of 40206691 is about 342.5832386885.

Adding to 40206691 its reverse (19660204), we get a palindrome (59866895).

The spelling of 40206691 in words is "forty million, two hundred six thousand, six hundred ninety-one".