21340060465 has 4 divisors (see below), whose sum is σ = 25608072564. Its totient is φ = 17072048368.

The previous prime is 21340060451. The next prime is 21340060481. The reversal of 21340060465 is 56406004312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16818977344 + 4521083121 = 129688^2 + 67239^2 .

It is a cyclic number.

It is not a de Polignac number, because 21340060465 - 2²⁵ = 21306506033 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2134006042 + ... + 2134006051.

It is an arithmetic number, because the mean of its divisors is an integer number (6402018141).

Almost surely, 2^21340060465 is an apocalyptic number.

It is an amenable number.

21340060465 is a deficient number, since it is larger than the sum of its proper divisors (4268012099).

21340060465 is an equidigital number, since it uses as much as digits as its factorization.

21340060465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4268012098.

The product of its (nonzero) digits is 17280, while the sum is 31.

Adding to 21340060465 its reverse (56406004312), we get a palindrome (77746064777).

The spelling of 21340060465 in words is "twenty-one billion, three hundred forty million, sixty thousand, four hundred sixty-five".