1221220021002 has 32 divisors (see below), whose sum is σ = 2453215766400. Its totient is φ = 405281065728.

The previous prime is 1221220020953. The next prime is 1221220021067. The reversal of 1221220021002 is 2001200221221.

It is a super-2 number, since 2×1221220021002² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 869574 + ... + 1788462.

It is an arithmetic number, because the mean of its divisors is an integer number (76662992700).

Almost surely, 2^{1221220021002} is an apocalyptic number.

1221220021002 is an abundant number, since it is smaller than the sum of its proper divisors (1231995745398).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221220021002 is a wasteful number, since it uses less digits than its factorization.

1221220021002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 919870.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 1221220021002 its reverse (2001200221221), we get a palindrome (3222420242223).

The spelling of 1221220021002 in words is "one trillion, two hundred twenty-one billion, two hundred twenty million, twenty-one thousand, two".