221121012511 has 16 divisors (see below), whose sum is σ = 267600291840. Its totient is φ = 178366481280.

The previous prime is 221121012479. The next prime is 221121012569. The reversal of 221121012511 is 115210121122.

It is a cyclic number.

It is not a de Polignac number, because 221121012511 - 2⁵ = 221121012479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221121012011) 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, 1263870 + ... + 1428148.

It is an arithmetic number, because the mean of its divisors is an integer number (16725018240).

Almost surely, 2^221121012511 is an apocalyptic number.

221121012511 is a deficient number, since it is larger than the sum of its proper divisors (46479279329).

221121012511 is a wasteful number, since it uses less digits than its factorization.

221121012511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175614.

The product of its (nonzero) digits is 80, while the sum is 19.

Adding to 221121012511 its reverse (115210121122), we get a palindrome (336331133633).

The spelling of 221121012511 in words is "two hundred twenty-one billion, one hundred twenty-one million, twelve thousand, five hundred eleven".