21063153651540 has 192 divisors, whose sum is σ = 79185674373120. Its totient is φ = 4040085404160.

The previous prime is 21063153651539. The next prime is 21063153651557. The reversal of 21063153651540 is 4515635136012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 21063153651492 and 21063153651501.

It is a congruent number.

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, 175290870 + ... + 175410989.

It is an arithmetic number, because the mean of its divisors is an integer number (412425387360).

Almost surely, 2^{21063153651540} is an apocalyptic number.

21063153651540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21063153651540 is an abundant number, since it is smaller than the sum of its proper divisors (58122520721580).

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

21063153651540 is a wasteful number, since it uses less digits than its factorization.

21063153651540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 350701902 (or 350701900 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 42.

Adding to 21063153651540 its reverse (4515635136012), we get a palindrome (25578788787552).

The spelling of 21063153651540 in words is "twenty-one trillion, sixty-three billion, one hundred fifty-three million, six hundred fifty-one thousand, five hundred forty".