21152164621523 has 8 divisors (see below), whose sum is σ = 22780802653728. Its totient is φ = 19523747795904.

The previous prime is 21152164621451. The next prime is 21152164621547. The reversal of 21152164621523 is 32512646125112.

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 21152164621523 - 2⁸ = 21152164621267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21152164641523) 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, 55103015 + ... + 55485552.

It is an arithmetic number, because the mean of its divisors is an integer number (2847600331716).

Almost surely, 2^{21152164621523} is an apocalyptic number.

21152164621523 is a deficient number, since it is larger than the sum of its proper divisors (1628638032205).

21152164621523 is a wasteful number, since it uses less digits than its factorization.

21152164621523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110603293.

The product of its digits is 172800, while the sum is 41.

The spelling of 21152164621523 in words is "twenty-one trillion, one hundred fifty-two billion, one hundred sixty-four million, six hundred twenty-one thousand, five hundred twenty-three".