21152535040 has 640 divisors, whose sum is σ = 67315691520. Its totient is φ = 6193152000.

The previous prime is 21152534993. The next prime is 21152535113. The reversal of 21152535040 is 4053525112.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (28).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 209430990 + ... + 209431090.

It is an arithmetic number, because the mean of its divisors is an integer number (105180768).

Almost surely, 2^21152535040 is an apocalyptic number.

21152535040 is a gapful number since it is divisible by the number (20) 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 21152535040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33657845760).

21152535040 is an abundant number, since it is smaller than the sum of its proper divisors (46163156480).

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

21152535040 is a wasteful number, since it uses less digits than its factorization.

21152535040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204 (or 188 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 28.

The spelling of 21152535040 in words is "twenty-one billion, one hundred fifty-two million, five hundred thirty-five thousand, forty".