1215215513525 has 24 divisors (see below), whose sum is σ = 1678738048680. Its totient is φ = 866445431040.

The previous prime is 1215215513497. The next prime is 1215215513563. The reversal of 1215215513525 is 5253155125121.

It can be written as a sum of positive squares in 12 ways, for example, as 863250966769 + 351964546756 = 929113^2 + 593266^2 .

It is not a de Polignac number, because 1215215513525 - 2¹⁴ = 1215215497141 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 64458242 + ... + 64477091.

It is an arithmetic number, because the mean of its divisors is an integer number (69947418695).

Almost surely, 2^{1215215513525} is an apocalyptic number.

It is an amenable number.

1215215513525 is a deficient number, since it is larger than the sum of its proper divisors (463522535155).

1215215513525 is a wasteful number, since it uses less digits than its factorization.

1215215513525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128935385 (or 128935380 counting only the distinct ones).

The product of its digits is 75000, while the sum is 38.

The spelling of 1215215513525 in words is "one trillion, two hundred fifteen billion, two hundred fifteen million, five hundred thirteen thousand, five hundred twenty-five".