16561051 has 8 divisors (see below), whose sum is σ = 17916080. Its totient is φ = 15217632.

The previous prime is 16561049. The next prime is 16561057. The reversal of 16561051 is 15016561.

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 16561051 - 2¹ = 16561049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16561057) 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, 196 + ... + 5758.

It is an arithmetic number, because the mean of its divisors is an integer number (2239510).

Almost surely, 2^16561051 is an apocalyptic number.

16561051 is a deficient number, since it is larger than the sum of its proper divisors (1355029).

16561051 is a wasteful number, since it uses less digits than its factorization.

16561051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5805.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 16561051 is about 4069.5271224062. The cubic root of 16561051 is about 254.8957718341.

It can be divided in two parts, 165 and 61051, that added together give a palindrome (61216).

The spelling of 16561051 in words is "sixteen million, five hundred sixty-one thousand, fifty-one".