1215066720021 has 64 divisors (see below), whose sum is σ = 2111705579520. Its totient is φ = 602604066240.

The previous prime is 1215066720001. The next prime is 1215066720061. The reversal of 1215066720021 is 1200276605121.

It is not a de Polignac number, because 1215066720021 - 2⁵ = 1215066719989 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215066720001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2560060 + ... + 2997338.

It is an arithmetic number, because the mean of its divisors is an integer number (32995399680).

Almost surely, 2^{1215066720021} is an apocalyptic number.

1215066720021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1215066720021 is a deficient number, since it is larger than the sum of its proper divisors (896638859499).

1215066720021 is a wasteful number, since it uses less digits than its factorization.

1215066720021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437846.

The product of its (nonzero) digits is 10080, while the sum is 33.

The spelling of 1215066720021 in words is "one trillion, two hundred fifteen billion, sixty-six million, seven hundred twenty thousand, twenty-one".