16509677893 has 4 divisors (see below), whose sum is σ = 16510246848. Its totient is φ = 16509108940.

The previous prime is 16509677869. The next prime is 16509677903. The reversal of 16509677893 is 39877690561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 39877690561 = 19 ⋅2098825819.

It is a cyclic number.

It is not a de Polignac number, because 16509677893 - 2⁵ = 16509677861 is a prime.

It is a super-2 number, since 2×16509677893² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16509677803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 238471 + ... + 299812.

It is an arithmetic number, because the mean of its divisors is an integer number (4127561712).

Almost surely, 2^16509677893 is an apocalyptic number.

It is an amenable number.

16509677893 is a deficient number, since it is larger than the sum of its proper divisors (568955).

16509677893 is an equidigital number, since it uses as much as digits as its factorization.

16509677893 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 568954.

The product of its (nonzero) digits is 17146080, while the sum is 61.

The spelling of 16509677893 in words is "sixteen billion, five hundred nine million, six hundred seventy-seven thousand, eight hundred ninety-three".