16038946561 has 4 divisors (see below), whose sum is σ = 17497032624. Its totient is φ = 14580860500.

The previous prime is 16038946559. The next prime is 16038946597. The reversal of 16038946561 is 16564983061.

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: 16564983061 = 11 ⋅1505907551.

It is a cyclic number.

It is not a de Polignac number, because 16038946561 - 2¹ = 16038946559 is a prime.

It is a super-2 number, since 2×16038946561² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16038946541) 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, 729043015 + ... + 729043036.

It is an arithmetic number, because the mean of its divisors is an integer number (4374258156).

Almost surely, 2^16038946561 is an apocalyptic number.

16038946561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16038946561 is a deficient number, since it is larger than the sum of its proper divisors (1458086063).

16038946561 is a wasteful number, since it uses less digits than its factorization.

16038946561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1458086062.

The product of its (nonzero) digits is 933120, while the sum is 49.

The spelling of 16038946561 in words is "sixteen billion, thirty-eight million, nine hundred forty-six thousand, five hundred sixty-one".