21545044501 has 8 divisors (see below), whose sum is σ = 22601894400. Its totient is φ = 20509122480.

The previous prime is 21545044489. The next prime is 21545044561. The reversal of 21545044501 is 10544054512.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21545044501 - 2²⁵ = 21511490069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21545044561) 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, 5229861 + ... + 5233978.

It is an arithmetic number, because the mean of its divisors is an integer number (2825236800).

Almost surely, 2^21545044501 is an apocalyptic number.

It is an amenable number.

21545044501 is a deficient number, since it is larger than the sum of its proper divisors (1056849899).

21545044501 is a wasteful number, since it uses less digits than its factorization.

21545044501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10463939.

The product of its (nonzero) digits is 16000, while the sum is 31.

The spelling of 21545044501 in words is "twenty-one billion, five hundred forty-five million, forty-four thousand, five hundred one".