2391521216 has 56 divisors (see below), whose sum is σ = 5435961696. Its totient is φ = 1022607360.

The previous prime is 2391521201. The next prime is 2391521219. The reversal of 2391521216 is 6121251932.

2391521216 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (56).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2391521219) 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, 198896 + ... + 210576.

Almost surely, 2^2391521216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2391521216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2717980848).

2391521216 is an abundant number, since it is smaller than the sum of its proper divisors (3044440480).

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

2391521216 is a wasteful number, since it uses less digits than its factorization.

2391521216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12157 (or 12147 counting only the distinct ones).

The product of its digits is 6480, while the sum is 32.

The square root of 2391521216 is about 48903.1820641561. The cubic root of 2391521216 is about 1337.2873794373.

The spelling of 2391521216 in words is "two billion, three hundred ninety-one million, five hundred twenty-one thousand, two hundred sixteen".