16051123621 has 16 divisors (see below), whose sum is σ = 17395246960. Its totient is φ = 14722767360.

The previous prime is 16051123589. The next prime is 16051123651. The reversal of 16051123621 is 12632115061.

16051123621 = 89585² + 89586².

It can be written as a sum of positive squares in 8 ways, for example, as 6349858596 + 9701265025 = 79686^2 + 98495^2 .

It is a 5-Lehmer number, since φ(16051123621) divides (16051123621-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 16051123621 - 2⁵ = 16051123589 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16051123621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16051123651) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4546585 + ... + 4550113.

It is an arithmetic number, because the mean of its divisors is an integer number (1087202935).

Almost surely, 2^16051123621 is an apocalyptic number.

16051123621 is the 89586-th centered square number.

It is an amenable number.

16051123621 is a deficient number, since it is larger than the sum of its proper divisors (1344123339).

16051123621 is a wasteful number, since it uses less digits than its factorization.

16051123621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5656.

The product of its (nonzero) digits is 2160, while the sum is 28.

Adding to 16051123621 its reverse (12632115061), we get a palindrome (28683238682).

The spelling of 16051123621 in words is "sixteen billion, fifty-one million, one hundred twenty-three thousand, six hundred twenty-one".