16405393681988 has 48 divisors (see below), whose sum is σ = 31047968818944. Its totient is φ = 7555203509760.

The previous prime is 16405393681961. The next prime is 16405393682033. The reversal of 16405393681988 is 88918639350461.

It is a happy number.

It is a super-2 number, since 2×16405393681988² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33928370 + ... + 34408502.

It is an arithmetic number, because the mean of its divisors is an integer number (646832683728).

Almost surely, 2^{16405393681988} is an apocalyptic number.

It is an amenable number.

16405393681988 is a deficient number, since it is larger than the sum of its proper divisors (14642575136956).

16405393681988 is a wasteful number, since it uses less digits than its factorization.

16405393681988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490892 (or 490890 counting only the distinct ones).

The product of its (nonzero) digits is 268738560, while the sum is 71.

The spelling of 16405393681988 in words is "sixteen trillion, four hundred five billion, three hundred ninety-three million, six hundred eighty-one thousand, nine hundred eighty-eight".