40455661 has 2 divisors, whose sum is σ = 40455662. Its totient is φ = 40455660.

The previous prime is 40455659. The next prime is 40455671. The reversal of 40455661 is 16655404.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39312900 + 1142761 = 6270^2 + 1069^2 .

It is a cyclic number.

It is not a de Polignac number, because 40455661 - 2¹ = 40455659 is a prime.

Together with 40455659, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40455601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20227830 + 20227831.

It is an arithmetic number, because the mean of its divisors is an integer number (20227831).

Almost surely, 2^40455661 is an apocalyptic number.

It is an amenable number.

40455661 is a deficient number, since it is larger than the sum of its proper divisors (1).

40455661 is an equidigital number, since it uses as much as digits as its factorization.

40455661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 40455661 is about 6360.4764758625. The cubic root of 40455661 is about 343.2889048196.

It can be divided in two parts, 404 and 55661, that added together give a palindrome (56065).

The spelling of 40455661 in words is "forty million, four hundred fifty-five thousand, six hundred sixty-one".