16165111501561 has 8 divisors (see below), whose sum is σ = 17718243716448. Its totient is φ = 14625908724000.

The previous prime is 16165111501493. The next prime is 16165111501577. The reversal of 16165111501561 is 16510511156161.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 16165111501561 - 2¹³ = 16165111493369 is a prime.

It is a super-2 number, since 2×16165111501561² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (16165111508561) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3482356900 + ... + 3482361541.

It is an arithmetic number, because the mean of its divisors is an integer number (2214780464556).

Almost surely, 2^{16165111501561} is an apocalyptic number.

16165111501561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16165111501561 is a deficient number, since it is larger than the sum of its proper divisors (1553132214887).

16165111501561 is a wasteful number, since it uses less digits than its factorization.

16165111501561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6964718663.

The product of its (nonzero) digits is 27000, while the sum is 40.

The spelling of 16165111501561 in words is "sixteen trillion, one hundred sixty-five billion, one hundred eleven million, five hundred one thousand, five hundred sixty-one".