1681996636 has 54 divisors (see below), whose sum is σ = 3171805728. Its totient is φ = 779617440.

The previous prime is 1681996621. The next prime is 1681996637. The reversal of 1681996636 is 6366991861.

It is a super-2 number, since 2×1681996636² = 5658225367030632992, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1681996637) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 13244005 + ... + 13244131.

Almost surely, 2^1681996636 is an apocalyptic number.

It is an amenable number.

1681996636 is a deficient number, since it is larger than the sum of its proper divisors (1489809092).

1681996636 is a wasteful number, since it uses less digits than its factorization.

1681996636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347 (or 189 counting only the distinct ones).

The product of its digits is 2519424, while the sum is 55.

The square root of 1681996636 is about 41012.1522966059. The cubic root of 1681996636 is about 1189.2551504777.

The spelling of 1681996636 in words is "one billion, six hundred eighty-one million, nine hundred ninety-six thousand, six hundred thirty-six".