66845649 has 16 divisors (see below), whose sum is σ = 101630592. Its totient is φ = 38715648.

The previous prime is 66845633. The next prime is 66845657. The reversal of 66845649 is 94654866.

It is a happy number.

It is not a de Polignac number, because 66845649 - 2⁴ = 66845633 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66845598 and 66845607.

It is not an unprimeable number, because it can be changed into a prime (66845689) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49749 + ... + 51074.

It is an arithmetic number, because the mean of its divisors is an integer number (6351912).

Almost surely, 2^66845649 is an apocalyptic number.

It is an amenable number.

66845649 is a deficient number, since it is larger than the sum of its proper divisors (34784943).

66845649 is a wasteful number, since it uses less digits than its factorization.

66845649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100856.

The product of its digits is 1244160, while the sum is 48.

The square root of 66845649 is about 8175.9188474446. The cubic root of 66845649 is about 405.8426776878.

The spelling of 66845649 in words is "sixty-six million, eight hundred forty-five thousand, six hundred forty-nine".