1640849207 has 4 divisors (see below), whose sum is σ = 1671808680. Its totient is φ = 1609889736.

The previous prime is 1640849191. The next prime is 1640849209. The reversal of 1640849207 is 7029480461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7029480461 = 163 ⋅43125647.

It is a cyclic number.

It is not a de Polignac number, because 1640849207 - 2⁴ = 1640849191 is a prime.

It is a super-2 number, since 2×1640849207² = 5384772240225057698, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640849209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15479657 + ... + 15479762.

It is an arithmetic number, because the mean of its divisors is an integer number (417952170).

Almost surely, 2^1640849207 is an apocalyptic number.

1640849207 is a deficient number, since it is larger than the sum of its proper divisors (30959473).

1640849207 is an equidigital number, since it uses as much as digits as its factorization.

1640849207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30959472.

The product of its (nonzero) digits is 96768, while the sum is 41.

The square root of 1640849207 is about 40507.3969417932. The cubic root of 1640849207 is about 1179.4772191088.

The spelling of 1640849207 in words is "one billion, six hundred forty million, eight hundred forty-nine thousand, two hundred seven".