21152666436665 has 8 divisors (see below), whose sum is σ = 25923267803520. Its totient is φ = 16562087762992.

The previous prime is 21152666436661. The next prime is 21152666436679. The reversal of 21152666436665 is 56663466625112.

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 21152666436665 - 2² = 21152666436661 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21152666436661) 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, 45005673035 + ... + 45005673504.

It is an arithmetic number, because the mean of its divisors is an integer number (3240408475440).

Almost surely, 2^{21152666436665} is an apocalyptic number.

It is an amenable number.

21152666436665 is a deficient number, since it is larger than the sum of its proper divisors (4770601366855).

21152666436665 is an equidigital number, since it uses as much as digits as its factorization.

21152666436665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90011346591.

The product of its digits is 55987200, while the sum is 59.

The spelling of 21152666436665 in words is "twenty-one trillion, one hundred fifty-two billion, six hundred sixty-six million, four hundred thirty-six thousand, six hundred sixty-five".