1215205330545 has 20 divisors (see below), whose sum is σ = 2178368074740. Its totient is φ = 648109509408.

The previous prime is 1215205330489. The next prime is 1215205330553. The reversal of 1215205330545 is 5450335025121.

1215205330545 is a `hidden beast` number, since 1 + 2 + 1 + 520 + 53 + 30 + 54 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 238968456336 + 976236874209 = 488844^2 + 988047^2 .

It is not a de Polignac number, because 1215205330545 - 2⁸ = 1215205330289 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1500253090 + ... + 1500253899.

It is an arithmetic number, because the mean of its divisors is an integer number (108918403737).

Almost surely, 2^{1215205330545} is an apocalyptic number.

1215205330545 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1215205330545 is a deficient number, since it is larger than the sum of its proper divisors (963162744195).

1215205330545 is an equidigital number, since it uses as much as digits as its factorization.

1215205330545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3000507006 (or 3000506997 counting only the distinct ones).

The product of its (nonzero) digits is 90000, while the sum is 36.

The spelling of 1215205330545 in words is "one trillion, two hundred fifteen billion, two hundred five million, three hundred thirty thousand, five hundred forty-five".