16921690648 has 8 divisors (see below), whose sum is σ = 31728169980. Its totient is φ = 8460845320.

The previous prime is 16921690619. The next prime is 16921690651. The reversal of 16921690648 is 84609612961.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-3 number, since 3×16921690648³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 16921690595 and 16921690604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1057605658 + ... + 1057605673.

Almost surely, 2^16921690648 is an apocalyptic number.

It is an amenable number.

16921690648 is a deficient number, since it is larger than the sum of its proper divisors (14806479332).

16921690648 is a wasteful number, since it uses less digits than its factorization.

16921690648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2115211337 (or 2115211333 counting only the distinct ones).

The product of its (nonzero) digits is 1119744, while the sum is 52.

The spelling of 16921690648 in words is "sixteen billion, nine hundred twenty-one million, six hundred ninety thousand, six hundred forty-eight".