221632453406 has 48 divisors (see below), whose sum is σ = 416801854224. Its totient is φ = 87609787776.

The previous prime is 221632453391. The next prime is 221632453439. The reversal of 221632453406 is 604354236122.

It is a super-2 number, since 2×221632453406² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 221632453406.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1566746 + ... + 1702338.

It is an arithmetic number, because the mean of its divisors is an integer number (8683371963).

Almost surely, 2^221632453406 is an apocalyptic number.

221632453406 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

221632453406 is a deficient number, since it is larger than the sum of its proper divisors (195169400818).

221632453406 is a wasteful number, since it uses less digits than its factorization.

221632453406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136905 (or 136898 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 38.

Adding to 221632453406 its reverse (604354236122), we get a palindrome (825986689528).

The spelling of 221632453406 in words is "two hundred twenty-one billion, six hundred thirty-two million, four hundred fifty-three thousand, four hundred six".