1221222220010 has 32 divisors (see below), whose sum is σ = 2367813848400. Its totient is φ = 450813477888.

The previous prime is 1221222220007. The next prime is 1221222220019. The reversal of 1221222220010 is 100222221221.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 493198602961 + 728023617049 = 702281^2 + 853243^2 .

It is not an unprimeable number, because it can be changed into a prime (1221222220019) 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, 441167 + ... + 1623906.

Almost surely, 2^{1221222220010} is an apocalyptic number.

1221222220010 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221222220010 is a deficient number, since it is larger than the sum of its proper divisors (1146591628390).

1221222220010 is a wasteful number, since it uses less digits than its factorization.

1221222220010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2069642.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 1221222220010 its reverse (100222221221), we get a palindrome (1321444441231).

The spelling of 1221222220010 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-two million, two hundred twenty thousand, ten".