221221213401 has 8 divisors (see below), whose sum is σ = 312312301344. Its totient is φ = 138805467200.

The previous prime is 221221213373. The next prime is 221221213501. The reversal of 221221213401 is 104312122122.

It is a happy number.

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 221221213401 - 2¹⁸ = 221220951257 is a prime.

It is a super-2 number, since 2×221221213401² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (221221213501) 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, 2168835375 + ... + 2168835476.

It is an arithmetic number, because the mean of its divisors is an integer number (39039037668).

Almost surely, 2^221221213401 is an apocalyptic number.

It is an amenable number.

221221213401 is a deficient number, since it is larger than the sum of its proper divisors (91091087943).

221221213401 is a wasteful number, since it uses less digits than its factorization.

221221213401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4337670871.

The product of its (nonzero) digits is 384, while the sum is 21.

Adding to 221221213401 its reverse (104312122122), we get a palindrome (325533335523).

The spelling of 221221213401 in words is "two hundred twenty-one billion, two hundred twenty-one million, two hundred thirteen thousand, four hundred one".