21340612365 has 16 divisors (see below), whose sum is σ = 35322393600. Its totient is φ = 10989188672.

The previous prime is 21340612357. The next prime is 21340612417. The reversal of 21340612365 is 56321604312.

It is a cyclic number.

It is not a de Polignac number, because 21340612365 - 2³ = 21340612357 is a prime.

It is a super-2 number, since 2×21340612365² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24529005 + ... + 24529874.

It is an arithmetic number, because the mean of its divisors is an integer number (2207649600).

Almost surely, 2^21340612365 is an apocalyptic number.

It is an amenable number.

21340612365 is a deficient number, since it is larger than the sum of its proper divisors (13981781235).

21340612365 is a wasteful number, since it uses less digits than its factorization.

21340612365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49058916.

The product of its (nonzero) digits is 25920, while the sum is 33.

It can be divided in two parts, 213 and 40612365, that added together give a triangular number (40612578 = T₉₀₁₂).

The spelling of 21340612365 in words is "twenty-one billion, three hundred forty million, six hundred twelve thousand, three hundred sixty-five".