866405690 has 16 divisors (see below), whose sum is σ = 1601680392. Its totient is φ = 337195584.

The previous prime is 866405689. The next prime is 866405693. The reversal of 866405690 is 96504668.

866405690 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 631366129 + 235039561 = 25127^2 + 15331^2 .

It is a super-2 number, since 2×866405690² = 1501317639328752200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (866405693) 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, 1170449 + ... + 1171188.

Almost surely, 2^866405690 is an apocalyptic number.

866405690 is a deficient number, since it is larger than the sum of its proper divisors (735274702).

866405690 is a wasteful number, since it uses less digits than its factorization.

866405690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2341681.

The product of its (nonzero) digits is 311040, while the sum is 44.

The square root of 866405690 is about 29434.7700857336. The cubic root of 866405690 is about 953.3237922932.

The spelling of 866405690 in words is "eight hundred sixty-six million, four hundred five thousand, six hundred ninety".