1221100121002 has 4 divisors (see below), whose sum is σ = 1831650181506. Its totient is φ = 610550060500.

The previous prime is 1221100120979. The next prime is 1221100121071. The reversal of 1221100121002 is 2001210011221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1221093510961 + 6610041 = 1105031^2 + 2571^2 .

It is a super-2 number, since 2×1221100121002² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305275030249 + ... + 305275030252.

Almost surely, 2^{1221100121002} is an apocalyptic number.

1221100121002 is a deficient number, since it is larger than the sum of its proper divisors (610550060504).

1221100121002 is an equidigital number, since it uses as much as digits as its factorization.

1221100121002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 610550060503.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 1221100121002 its reverse (2001210011221), we get a palindrome (3222310132223).

The spelling of 1221100121002 in words is "one trillion, two hundred twenty-one billion, one hundred million, one hundred twenty-one thousand, two".