21100506001 has 8 divisors (see below), whose sum is σ = 21314879208. Its totient is φ = 20886240000.

The previous prime is 21100505989. The next prime is 21100506023. The reversal of 21100506001 is 10060500112.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 13188225600 + 7912280401 = 114840^2 + 88951^2 .

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 21100506001 - 2¹¹ = 21100503953 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21100506041) 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, 403711 + ... + 452971.

It is an arithmetic number, because the mean of its divisors is an integer number (2664359901).

Almost surely, 2^21100506001 is an apocalyptic number.

It is an amenable number.

21100506001 is a deficient number, since it is larger than the sum of its proper divisors (214373207).

21100506001 is a wasteful number, since it uses less digits than its factorization.

21100506001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53603.

The product of its (nonzero) digits is 60, while the sum is 16.

The spelling of 21100506001 in words is "twenty-one billion, one hundred million, five hundred six thousand, one".