221806402051 has 8 divisors (see below), whose sum is σ = 245324337104. Its totient is φ = 199210739040.

The previous prime is 221806402049. The next prime is 221806402061. The reversal of 221806402051 is 150204608122.

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 221806402051 - 2¹ = 221806402049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221806402061) 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, 230567505 + ... + 230568466.

It is an arithmetic number, because the mean of its divisors is an integer number (30665542138).

Almost surely, 2^221806402051 is an apocalyptic number.

221806402051 is a deficient number, since it is larger than the sum of its proper divisors (23517935053).

221806402051 is a wasteful number, since it uses less digits than its factorization.

221806402051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 461136021.

The product of its (nonzero) digits is 7680, while the sum is 31.

The spelling of 221806402051 in words is "two hundred twenty-one billion, eight hundred six million, four hundred two thousand, fifty-one".