1681578252 has 24 divisors (see below), whose sum is σ = 4359647600. Its totient is φ = 560526048.

The previous prime is 1681578221. The next prime is 1681578289. The reversal of 1681578252 is 2528751861.

It is a junction number, because it is equal to n+sod(n) for n = 1681578198 and 1681578207.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7784977 + ... + 7785192.

Almost surely, 2^1681578252 is an apocalyptic number.

1681578252 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1681578252 is an abundant number, since it is smaller than the sum of its proper divisors (2678069348).

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

1681578252 is a wasteful number, since it uses less digits than its factorization.

1681578252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15570182 (or 15570174 counting only the distinct ones).

The product of its digits is 268800, while the sum is 45.

The square root of 1681578252 is about 41007.0512473160. The cubic root of 1681578252 is about 1189.1565362123.

The spelling of 1681578252 in words is "one billion, six hundred eighty-one million, five hundred seventy-eight thousand, two hundred fifty-two".