849649840 has 40 divisors (see below), whose sum is σ = 2127395088. Its totient is φ = 313716480.

The previous prime is 849649799. The next prime is 849649873. The reversal of 849649840 is 48946948.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×849649840² = 1443809701224051200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (52).

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 7 ways as a sum of consecutive naturals, for example, 407446 + ... + 409525.

Almost surely, 2^849649840 is an apocalyptic number.

849649840 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

849649840 is an abundant number, since it is smaller than the sum of its proper divisors (1277745248).

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

849649840 is a wasteful number, since it uses less digits than its factorization.

849649840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 816997 (or 816991 counting only the distinct ones).

The product of its (nonzero) digits is 1990656, while the sum is 52.

The square root of 849649840 is about 29148.7536611774. The cubic root of 849649840 is about 947.1381426745.

The spelling of 849649840 in words is "eight hundred forty-nine million, six hundred forty-nine thousand, eight hundred forty".