1643658460 has 24 divisors (see below), whose sum is σ = 3633351120. Its totient is φ = 622859904.

The previous prime is 1643658451. The next prime is 1643658461. The reversal of 1643658460 is 648563461.

It is a happy number.

It is a super-2 number, since 2×1643658460² = 5403226266259143200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (43) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643658461) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2162329 + ... + 2163088.

It is an arithmetic number, because the mean of its divisors is an integer number (151389630).

Almost surely, 2^1643658460 is an apocalyptic number.

1643658460 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1643658460 is an abundant number, since it is smaller than the sum of its proper divisors (1989692660).

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

1643658460 is a wasteful number, since it uses less digits than its factorization.

1643658460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4325445 (or 4325443 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 43.

The square root of 1643658460 is about 40542.0579152070. The cubic root of 1643658460 is about 1180.1499522162.

The spelling of 1643658460 in words is "one billion, six hundred forty-three million, six hundred fifty-eight thousand, four hundred sixty".