215030521440 has 144 divisors (see below), whose sum is σ = 838619072928. Its totient is φ = 49149831168.

The previous prime is 215030521411. The next prime is 215030521457. The reversal of 215030521440 is 44125030512.

215030521440 is a `hidden beast` number, since 21 + 50 + 30 + 521 + 4 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

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, 10656117 + ... + 10676276.

It is an arithmetic number, because the mean of its divisors is an integer number (5823743562).

Almost surely, 2^215030521440 is an apocalyptic number.

215030521440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215030521440 is an abundant number, since it is smaller than the sum of its proper divisors (623588551488).

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

215030521440 is a wasteful number, since it uses less digits than its factorization.

215030521440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21332421 (or 21332410 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

Adding to 215030521440 its reverse (44125030512), we get a palindrome (259155551952).

The spelling of 215030521440 in words is "two hundred fifteen billion, thirty million, five hundred twenty-one thousand, four hundred forty".