2158521984 has 192 divisors, whose sum is σ = 6462261000. Its totient is φ = 690978816.

The previous prime is 2158521941. The next prime is 2158522001. The reversal of 2158521984 is 4891258512.

It can be written as a sum of positive squares in 4 ways, for example, as 1635393600 + 523128384 = 40440^2 + 22872^2 .

It is a tau number, because it is divible by the number of its divisors (192).

It is a super-2 number, since 2×2158521984² = 9318434310822592512, which contains 22 as substring.

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, 3793252 + ... + 3793820.

Almost surely, 2^2158521984 is an apocalyptic number.

2158521984 is a gapful number since it is divisible by the number (24) 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 2158521984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3231130500).

2158521984 is an abundant number, since it is smaller than the sum of its proper divisors (4303739016).

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

2158521984 is a wasteful number, since it uses less digits than its factorization.

2158521984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 715 (or 700 counting only the distinct ones).

The product of its digits is 230400, while the sum is 45.

The square root of 2158521984 is about 46459.8965130143. The cubic root of 2158521984 is about 1292.3659051747.

The spelling of 2158521984 in words is "two billion, one hundred fifty-eight million, five hundred twenty-one thousand, nine hundred eighty-four".