21505663041 has 8 divisors (see below), whose sum is σ = 28866662400. Its totient is φ = 14240886192.

The previous prime is 21505663013. The next prime is 21505663061. The reversal of 21505663041 is 14036650512.

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

It is not a de Polignac number, because 21505663041 - 2⁶ = 21505662977 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21505662993 and 21505663011.

It is not an unprimeable number, because it can be changed into a prime (21505663061) 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, 24055105 + ... + 24055998.

It is an arithmetic number, because the mean of its divisors is an integer number (3608332800).

Almost surely, 2^21505663041 is an apocalyptic number.

It is an amenable number.

21505663041 is a deficient number, since it is larger than the sum of its proper divisors (7360999359).

21505663041 is a wasteful number, since it uses less digits than its factorization.

21505663041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48111255.

The product of its (nonzero) digits is 21600, while the sum is 33.

The spelling of 21505663041 in words is "twenty-one billion, five hundred five million, six hundred sixty-three thousand, forty-one".