21520011120425 has 48 divisors (see below), whose sum is σ = 27280912374144. Its totient is φ = 16835757120000.

The previous prime is 21520011120397. The next prime is 21520011120473. The reversal of 21520011120425 is 52402111002512.

It is a happy number.

It is not a de Polignac number, because 21520011120425 - 2²⁴ = 21519994343209 is a prime.

It is a super-2 number, since 2×21520011120425² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21520011120394 and 21520011120403.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 159055805 + ... + 159191045.

It is an arithmetic number, because the mean of its divisors is an integer number (568352341128).

Almost surely, 2^{21520011120425} is an apocalyptic number.

21520011120425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21520011120425 is a deficient number, since it is larger than the sum of its proper divisors (5760901253719).

21520011120425 is a wasteful number, since it uses less digits than its factorization.

21520011120425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136050 (or 136045 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 26.

Adding to 21520011120425 its reverse (52402111002512), we get a palindrome (73922122122937).

The spelling of 21520011120425 in words is "twenty-one trillion, five hundred twenty billion, eleven million, one hundred twenty thousand, four hundred twenty-five".