21355506001 has 8 divisors (see below), whose sum is σ = 21511736064. Its totient is φ = 21199696560.

The previous prime is 21355505987. The next prime is 21355506031. The reversal of 21355506001 is 10060555312.

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 21355506001 - 2²¹ = 21353408849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21355506031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2881 + ... + 206686.

It is an arithmetic number, because the mean of its divisors is an integer number (2688967008).

Almost surely, 2^21355506001 is an apocalyptic number.

It is an amenable number.

21355506001 is a deficient number, since it is larger than the sum of its proper divisors (156230063).

21355506001 is a wasteful number, since it uses less digits than its factorization.

21355506001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210311.

The product of its (nonzero) digits is 4500, while the sum is 28.

The spelling of 21355506001 in words is "twenty-one billion, three hundred fifty-five million, five hundred six thousand, one".