221435220831 has 16 divisors (see below), whose sum is σ = 336091403520. Its totient is φ = 128368243520.

The previous prime is 221435220803. The next prime is 221435220847. The reversal of 221435220831 is 138022534122.

It is not a de Polignac number, because 221435220831 - 2⁷ = 221435220703 is a prime.

It is a super-2 number, since 2×221435220831² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 221435220792 and 221435220801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221435220031) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 145872246 + ... + 145873763.

It is an arithmetic number, because the mean of its divisors is an integer number (21005712720).

Almost surely, 2^221435220831 is an apocalyptic number.

221435220831 is a deficient number, since it is larger than the sum of its proper divisors (114656182689).

221435220831 is a wasteful number, since it uses less digits than its factorization.

221435220831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 291746046.

The product of its (nonzero) digits is 23040, while the sum is 33.

Adding to 221435220831 its reverse (138022534122), we get a palindrome (359457754953).

The spelling of 221435220831 in words is "two hundred twenty-one billion, four hundred thirty-five million, two hundred twenty thousand, eight hundred thirty-one".