1221111001210 has 32 divisors (see below), whose sum is σ = 2206233611712. Its totient is φ = 486618088320.

The previous prime is 1221111001151. The next prime is 1221111001237. The reversal of 1221111001210 is 121001111221.

It is a happy number.

It is a super-2 number, since 2×1221111001210² (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, 2647390 + ... + 3074230.

It is an arithmetic number, because the mean of its divisors is an integer number (68944800366).

Almost surely, 2^{1221111001210} is an apocalyptic number.

1221111001210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221111001210 is a deficient number, since it is larger than the sum of its proper divisors (985122610502).

1221111001210 is a wasteful number, since it uses less digits than its factorization.

1221111001210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 427918.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 1221111001210 its reverse (121001111221), we get a palindrome (1342112112431).

The spelling of 1221111001210 in words is "one trillion, two hundred twenty-one billion, one hundred eleven million, one thousand, two hundred ten".