1221000100106 has 16 divisors (see below), whose sum is σ = 1853919763584. Its totient is φ = 603050914944.

The previous prime is 1221000100091. The next prime is 1221000100121. The reversal of 1221000100106 is 6010010001221.

It is an interprime number because it is at equal distance from previous prime (1221000100091) and next prime (1221000100121).

It is a super-2 number, since 2×1221000100106² (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 7 ways as a sum of consecutive naturals, for example, 5915570 + ... + 6118493.

It is an arithmetic number, because the mean of its divisors is an integer number (115869985224).

Almost surely, 2^{1221000100106} is an apocalyptic number.

1221000100106 is a deficient number, since it is larger than the sum of its proper divisors (632919663478).

1221000100106 is a wasteful number, since it uses less digits than its factorization.

1221000100106 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12034685.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 1221000100106 its reverse (6010010001221), we get a palindrome (7231010101327).

The spelling of 1221000100106 in words is "one trillion, two hundred twenty-one billion, one hundred thousand, one hundred six".