1640969786 has 8 divisors (see below), whose sum is σ = 2462840544. Its totient is φ = 820022940.

The previous prime is 1640969767. The next prime is 1640969801. The reversal of 1640969786 is 6879690461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 226520 + ... + 233651.

It is an arithmetic number, because the mean of its divisors is an integer number (307855068).

Almost surely, 2^1640969786 is an apocalyptic number.

1640969786 is a deficient number, since it is larger than the sum of its proper divisors (821870758).

1640969786 is a wasteful number, since it uses less digits than its factorization.

1640969786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 461956.

The product of its (nonzero) digits is 3919104, while the sum is 56.

The square root of 1640969786 is about 40508.8852722461. The cubic root of 1640969786 is about 1179.5061099822.

The spelling of 1640969786 in words is "one billion, six hundred forty million, nine hundred sixty-nine thousand, seven hundred eighty-six".