1221404512125 has 32 divisors (see below), whose sum is σ = 2322762414336. Its totient is φ = 558356347200.

The previous prime is 1221404512121. The next prime is 1221404512169. The reversal of 1221404512125 is 5212154041221.

It is not a de Polignac number, because 1221404512125 - 2² = 1221404512121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1221404512092 and 1221404512101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221404512121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 232645854 + ... + 232651103.

It is an arithmetic number, because the mean of its divisors is an integer number (72586325448).

Almost surely, 2^{1221404512125} is an apocalyptic number.

1221404512125 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1221404512125 is a deficient number, since it is larger than the sum of its proper divisors (1101357902211).

1221404512125 is an equidigital number, since it uses as much as digits as its factorization.

1221404512125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 465296982 (or 465296972 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 30.

Adding to 1221404512125 its reverse (5212154041221), we get a palindrome (6433558553346).

The spelling of 1221404512125 in words is "one trillion, two hundred twenty-one billion, four hundred four million, five hundred twelve thousand, one hundred twenty-five".