1221148478121 has 32 divisors (see below), whose sum is σ = 1974552760320. Its totient is φ = 661122561600.

The previous prime is 1221148478107. The next prime is 1221148478189. The reversal of 1221148478121 is 1218748411221.

It is a happy number.

It is not a de Polignac number, because 1221148478121 - 2⁶ = 1221148478057 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1221148474121) 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, 45897991 + ... + 45924588.

It is an arithmetic number, because the mean of its divisors is an integer number (61704773760).

Almost surely, 2^{1221148478121} is an apocalyptic number.

1221148478121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221148478121 is a deficient number, since it is larger than the sum of its proper divisors (753404282199).

1221148478121 is a wasteful number, since it uses less digits than its factorization.

1221148478121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91822637.

The product of its digits is 57344, while the sum is 42.

The spelling of 1221148478121 in words is "one trillion, two hundred twenty-one billion, one hundred forty-eight million, four hundred seventy-eight thousand, one hundred twenty-one".