70821666 has 12 divisors (see below), whose sum is σ = 153446982. Its totient is φ = 23607216.

The previous prime is 70821649. The next prime is 70821689. The reversal of 70821666 is 66612807.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 65853225 + 4968441 = 8115^2 + 2229^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 70821666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1967251 + ... + 1967286.

Almost surely, 2^70821666 is an apocalyptic number.

70821666 is an abundant number, since it is smaller than the sum of its proper divisors (82625316).

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

70821666 is a wasteful number, since it uses less digits than its factorization.

70821666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3934545 (or 3934542 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 70821666 is about 8415.5609438706. The cubic root of 70821666 is about 413.7347947911.

The spelling of 70821666 in words is "seventy million, eight hundred twenty-one thousand, six hundred sixty-six".