21436647557513 has 8 divisors (see below), whose sum is σ = 22722651788832. Its totient is φ = 20153423877696.

The previous prime is 21436647557461. The next prime is 21436647557573. The reversal of 21436647557513 is 31575574663412.

It is a happy number.

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 21436647557513 - 2⁸ = 21436647557257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21436647557573) 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, 695121995 + ... + 695152832.

It is an arithmetic number, because the mean of its divisors is an integer number (2840331473604).

Almost surely, 2^{21436647557513} is an apocalyptic number.

It is an amenable number.

21436647557513 is a deficient number, since it is larger than the sum of its proper divisors (1286004231319).

21436647557513 is a wasteful number, since it uses less digits than its factorization.

21436647557513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1390275751.

The product of its digits is 63504000, while the sum is 59.

The spelling of 21436647557513 in words is "twenty-one trillion, four hundred thirty-six billion, six hundred forty-seven million, five hundred fifty-seven thousand, five hundred thirteen".