21450235145 has 16 divisors (see below), whose sum is σ = 26462395920. Its totient is φ = 16679706624.

The previous prime is 21450235097. The next prime is 21450235153. The reversal of 21450235145 is 54153205412.

It can be written as a sum of positive squares in 8 ways, for example, as 4682896 + 21445552249 = 2164^2 + 146443^2 .

It is a cyclic number.

It is not a de Polignac number, because 21450235145 - 2²² = 21446040841 is a prime.

It is a super-2 number, since 2×21450235145² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 129209 + ... + 244121.

It is an arithmetic number, because the mean of its divisors is an integer number (1653899745).

Almost surely, 2^21450235145 is an apocalyptic number.

It is an amenable number.

21450235145 is a deficient number, since it is larger than the sum of its proper divisors (5012160775).

21450235145 is a wasteful number, since it uses less digits than its factorization.

21450235145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115964.

The product of its (nonzero) digits is 24000, while the sum is 32.

The spelling of 21450235145 in words is "twenty-one billion, four hundred fifty million, two hundred thirty-five thousand, one hundred forty-five".