40697021 has 2 divisors, whose sum is σ = 40697022. Its totient is φ = 40697020.

The previous prime is 40697011. The next prime is 40697053. The reversal of 40697021 is 12079604.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 32205625 + 8491396 = 5675^2 + 2914^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40697021 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40697011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20348510 + 20348511.

It is an arithmetic number, because the mean of its divisors is an integer number (20348511).

Almost surely, 2^40697021 is an apocalyptic number.

It is an amenable number.

40697021 is a deficient number, since it is larger than the sum of its proper divisors (1).

40697021 is an equidigital number, since it uses as much as digits as its factorization.

40697021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 40697021 is about 6379.4216822530. The cubic root of 40697021 is about 343.9702431670.

The spelling of 40697021 in words is "forty million, six hundred ninety-seven thousand, twenty-one".