21623522061553 has 8 divisors (see below), whose sum is σ = 22564044554688. Its totient is φ = 20683030348464.

The previous prime is 21623522061517. The next prime is 21623522061571. The reversal of 21623522061553 is 35516022532612.

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 21623522061553 - 2¹⁷ = 21623521930481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21623522001553) 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, 6253675 + ... + 9074992.

It is an arithmetic number, because the mean of its divisors is an integer number (2820505569336).

Almost surely, 2^{21623522061553} is an apocalyptic number.

21623522061553 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21623522061553 is a deficient number, since it is larger than the sum of its proper divisors (940522493135).

21623522061553 is a wasteful number, since it uses less digits than its factorization.

21623522061553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15390023.

The product of its (nonzero) digits is 648000, while the sum is 43.

The spelling of 21623522061553 in words is "twenty-one trillion, six hundred twenty-three billion, five hundred twenty-two million, sixty-one thousand, five hundred fifty-three".