40644437 has 2 divisors, whose sum is σ = 40644438. Its totient is φ = 40644436.

The previous prime is 40644421. The next prime is 40644469. The reversal of 40644437 is 73444604.

It is an a-pointer prime, because the next prime (40644469) can be obtained adding 40644437 to its sum of digits (32).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35509681 + 5134756 = 5959^2 + 2266^2 .

It is a cyclic number.

It is not a de Polignac number, because 40644437 - 2⁴ = 40644421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40644337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20322218 + 20322219.

It is an arithmetic number, because the mean of its divisors is an integer number (20322219).

Almost surely, 2^40644437 is an apocalyptic number.

It is an amenable number.

40644437 is a deficient number, since it is larger than the sum of its proper divisors (1).

40644437 is an equidigital number, since it uses as much as digits as its factorization.

40644437 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32256, while the sum is 32.

The square root of 40644437 is about 6375.2989733816. The cubic root of 40644437 is about 343.8220330807.

The spelling of 40644437 in words is "forty million, six hundred forty-four thousand, four hundred thirty-seven".