121311321021 has 48 divisors (see below), whose sum is σ = 193453428480. Its totient is φ = 73248753600.

The previous prime is 121311321013. The next prime is 121311321031. The reversal of 121311321021 is 120123113121.

121311321021 is a `hidden beast` number, since 12 + 1 + 311 + 321 + 0 + 21 = 666.

It is not a de Polignac number, because 121311321021 - 2³ = 121311321013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121311320985 and 121311321003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121311321031) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3227625 + ... + 3264993.

It is an arithmetic number, because the mean of its divisors is an integer number (4030279760).

Almost surely, 2^121311321021 is an apocalyptic number.

121311321021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121311321021 is a deficient number, since it is larger than the sum of its proper divisors (72142107459).

121311321021 is a wasteful number, since it uses less digits than its factorization.

121311321021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37679 (or 37654 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

Adding to 121311321021 its reverse (120123113121), we get a palindrome (241434434142).

The spelling of 121311321021 in words is "one hundred twenty-one billion, three hundred eleven million, three hundred twenty-one thousand, twenty-one".