1021155213545 has 4 divisors (see below), whose sum is σ = 1225386256260. Its totient is φ = 816924170832.

The previous prime is 1021155213521. The next prime is 1021155213571. The reversal of 1021155213545 is 5453125511201.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 383180808256 + 637974405289 = 619016^2 + 798733^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021155213545 - 2²² = 1021151019241 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102115521350 + ... + 102115521359.

It is an arithmetic number, because the mean of its divisors is an integer number (306346564065).

Almost surely, 2^{1021155213545} is an apocalyptic number.

It is an amenable number.

1021155213545 is a deficient number, since it is larger than the sum of its proper divisors (204231042715).

1021155213545 is an equidigital number, since it uses as much as digits as its factorization.

1021155213545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204231042714.

The product of its (nonzero) digits is 30000, while the sum is 35.

The spelling of 1021155213545 in words is "one trillion, twenty-one billion, one hundred fifty-five million, two hundred thirteen thousand, five hundred forty-five".