66786740 has 24 divisors (see below), whose sum is σ = 143515680. Its totient is φ = 26093088.

The previous prime is 66786737. The next prime is 66786749. The reversal of 66786740 is 4768766.

It is a junction number, because it is equal to n+sod(n) for n = 66786691 and 66786700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66786749) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37970 + ... + 39689.

It is an arithmetic number, because the mean of its divisors is an integer number (5979820).

Almost surely, 2^66786740 is an apocalyptic number.

It is an amenable number.

66786740 is an abundant number, since it is smaller than the sum of its proper divisors (76728940).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66786740 is a wasteful number, since it uses less digits than its factorization.

66786740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77711 (or 77709 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 44.

The square root of 66786740 is about 8172.3154613610. The cubic root of 66786740 is about 405.7234237888.

The spelling of 66786740 in words is "sixty-six million, seven hundred eighty-six thousand, seven hundred forty".