121345043521 has 6 divisors (see below), whose sum is σ = 131397295830. Its totient is φ = 112010809248.

The previous prime is 121345043497. The next prime is 121345043537. The reversal of 121345043521 is 125340543121.

It can be written as a sum of positive squares in 3 ways, for example, as 991557121 + 120353486400 = 31489^2 + 346920^2 .

It is not a de Polignac number, because 121345043521 - 2²⁹ = 120808172609 is a prime.

It is a super-2 number, since 2×121345043521² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121345043021) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 359008836 + ... + 359009173.

It is an arithmetic number, because the mean of its divisors is an integer number (21899549305).

Almost surely, 2^121345043521 is an apocalyptic number.

It is an amenable number.

121345043521 is a deficient number, since it is larger than the sum of its proper divisors (10052252309).

121345043521 is an equidigital number, since it uses as much as digits as its factorization.

121345043521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 718018035 (or 718018022 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

Adding to 121345043521 its reverse (125340543121), we get a palindrome (246685586642).

The spelling of 121345043521 in words is "one hundred twenty-one billion, three hundred forty-five million, forty-three thousand, five hundred twenty-one".