1215428520 has 32 divisors (see below), whose sum is σ = 3646285920. Its totient is φ = 324114240.

The previous prime is 1215428471. The next prime is 1215428521. The reversal of 1215428520 is 258245121.

1215428520 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (1215428521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5064166 + ... + 5064405.

It is an arithmetic number, because the mean of its divisors is an integer number (113946435).

Almost surely, 2^1215428520 is an apocalyptic number.

1215428520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1215428520 is an abundant number, since it is smaller than the sum of its proper divisors (2430857400).

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

1215428520 is a wasteful number, since it uses less digits than its factorization.

1215428520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10128585 (or 10128581 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 30.

The square root of 1215428520 is about 34862.9964288786. The cubic root of 1215428520 is about 1067.1934251547.

The spelling of 1215428520 in words is "one billion, two hundred fifteen million, four hundred twenty-eight thousand, five hundred twenty".