66990843 has 24 divisors (see below), whose sum is σ = 100560096. Its totient is φ = 42940800.

The previous prime is 66990823. The next prime is 66990851. The reversal of 66990843 is 34809966.

It is not a de Polignac number, because 66990843 - 2⁸ = 66990587 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66990823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24921 + ... + 27477.

It is an arithmetic number, because the mean of its divisors is an integer number (4190004).

Almost surely, 2^66990843 is an apocalyptic number.

66990843 is a deficient number, since it is larger than the sum of its proper divisors (33569253).

66990843 is a wasteful number, since it uses less digits than its factorization.

66990843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2675 (or 2672 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

The square root of 66990843 is about 8184.7933999582. The cubic root of 66990843 is about 406.1363059200.

The spelling of 66990843 in words is "sixty-six million, nine hundred ninety thousand, eight hundred forty-three".