221201011028 has 12 divisors (see below), whose sum is σ = 392404533780. Its totient is φ = 109085429952.

The previous prime is 221201011027. The next prime is 221201011081. The reversal of 221201011028 is 820110102122.

It can be written as a sum of positive squares in 2 ways, for example, as 138204010564 + 82997000464 = 371758^2 + 288092^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221201011021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 378768563 + ... + 378769146.

It is an arithmetic number, because the mean of its divisors is an integer number (32700377815).

Almost surely, 2^221201011028 is an apocalyptic number.

It is an amenable number.

221201011028 is a deficient number, since it is larger than the sum of its proper divisors (171203522752).

221201011028 is a wasteful number, since it uses less digits than its factorization.

221201011028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 757537786 (or 757537784 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

The spelling of 221201011028 in words is "two hundred twenty-one billion, two hundred one million, eleven thousand, twenty-eight".