16620051081 has 4 divisors (see below), whose sum is σ = 22160068112. Its totient is φ = 11080034052.

The previous prime is 16620051073. The next prime is 16620051103. The reversal of 16620051081 is 18015002661.

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: 18015002661 = 3 ⋅6005000887.

It is not a de Polignac number, because 16620051081 - 2³ = 16620051073 is a prime.

It is a super-2 number, since 2×16620051081² (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 (16620151081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2770008511 + ... + 2770008516.

It is an arithmetic number, because the mean of its divisors is an integer number (5540017028).

Almost surely, 2^16620051081 is an apocalyptic number.

It is an amenable number.

16620051081 is a deficient number, since it is larger than the sum of its proper divisors (5540017031).

16620051081 is an equidigital number, since it uses as much as digits as its factorization.

16620051081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5540017030.

The product of its (nonzero) digits is 2880, while the sum is 30.

The spelling of 16620051081 in words is "sixteen billion, six hundred twenty million, fifty-one thousand, eighty-one".