20215422540 has 72 divisors (see below), whose sum is σ = 61445271888. Its totient is φ = 5379776640.

The previous prime is 20215422523. The next prime is 20215422541. The reversal of 20215422540 is 4522451202.

20215422540 is a `hidden beast` number, since 20 + 215 + 422 + 5 + 4 + 0 = 666.

It is not an unprimeable number, because it can be changed into a prime (20215422541) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25987 + ... + 202746.

It is an arithmetic number, because the mean of its divisors is an integer number (853406554).

Almost surely, 2^20215422540 is an apocalyptic number.

20215422540 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 20215422540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30722635944).

20215422540 is an abundant number, since it is smaller than the sum of its proper divisors (41229849348).

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

20215422540 is a wasteful number, since it uses less digits than its factorization.

20215422540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229239 (or 229234 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 27.

Adding to 20215422540 its reverse (4522451202), we get a palindrome (24737873742).

The spelling of 20215422540 in words is "twenty billion, two hundred fifteen million, four hundred twenty-two thousand, five hundred forty".