42105649 has 2 divisors, whose sum is σ = 42105650. Its totient is φ = 42105648.

The previous prime is 42105641. The next prime is 42105689. The reversal of 42105649 is 94650124.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41216400 + 889249 = 6420^2 + 943^2 .

It is a cyclic number.

It is not a de Polignac number, because 42105649 - 2³ = 42105641 is a prime.

It is a super-2 number, since 2×42105649² = 3545771355422402, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 42105649.

It is not a weakly prime, because it can be changed into another prime (42105641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21052824 + 21052825.

It is an arithmetic number, because the mean of its divisors is an integer number (21052825).

Almost surely, 2^42105649 is an apocalyptic number.

It is an amenable number.

42105649 is a deficient number, since it is larger than the sum of its proper divisors (1).

42105649 is an equidigital number, since it uses as much as digits as its factorization.

42105649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 42105649 is about 6488.8865762933. The cubic root of 42105649 is about 347.8938797623.

The spelling of 42105649 in words is "forty-two million, one hundred five thousand, six hundred forty-nine".