1215001251520 has 224 divisors, whose sum is σ = 3430769546880. Its totient is φ = 401006592000.

The previous prime is 1215001251517. The next prime is 1215001251551. The reversal of 1215001251520 is 251521005121.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (224).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21863770 + ... + 21919270.

Almost surely, 2^{1215001251520} is an apocalyptic number.

1215001251520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1215001251520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1715384773440).

1215001251520 is an abundant number, since it is smaller than the sum of its proper divisors (2215768295360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1215001251520 is a wasteful number, since it uses less digits than its factorization.

1215001251520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55891 (or 55881 counting only the distinct ones).

The product of its (nonzero) digits is 1000, while the sum is 25.

Adding to 1215001251520 its reverse (251521005121), we get a palindrome (1466522256641).

It can be divided in two parts, 1215001 and 251520, that added together give a square (1466521 = 1211²).

The spelling of 1215001251520 in words is "one trillion, two hundred fifteen billion, one million, two hundred fifty-one thousand, five hundred twenty".