16686821454925 has 12 divisors (see below), whose sum is σ = 20691745202080. Its totient is φ = 13349401294320.

The previous prime is 16686821454913. The next prime is 16686821454943. The reversal of 16686821454925 is 52945412868661.

It is a happy number.

It is not a de Polignac number, because 16686821454925 - 2¹⁵ = 16686821422157 is a prime.

It is a hoax number, since the sum of its digits (67) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5331766 + ... + 7861384.

Almost surely, 2^{16686821454925} is an apocalyptic number.

It is an amenable number.

16686821454925 is a deficient number, since it is larger than the sum of its proper divisors (4004923747155).

16686821454925 is a wasteful number, since it uses less digits than its factorization.

16686821454925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2793492 (or 2793487 counting only the distinct ones).

The product of its digits is 199065600, while the sum is 67.

The spelling of 16686821454925 in words is "sixteen trillion, six hundred eighty-six billion, eight hundred twenty-one million, four hundred fifty-four thousand, nine hundred twenty-five".