21221533514425 has 48 divisors (see below), whose sum is σ = 27109710461232. Its totient is φ = 16471730995200.

The previous prime is 21221533514411. The next prime is 21221533514449. The reversal of 21221533514425 is 52441533512212.

It can be written as a sum of positive squares in 24 ways, for example, as 2572289914896 + 18649243599529 = 1603836^2 + 4318477^2 .

It is not a de Polignac number, because 21221533514425 - 2³³ = 21212943579833 is a prime.

It is a Duffinian number.

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, 158918685 + ... + 159052165.

It is an arithmetic number, because the mean of its divisors is an integer number (564785634609).

Almost surely, 2^{21221533514425} is an apocalyptic number.

21221533514425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21221533514425 is a deficient number, since it is larger than the sum of its proper divisors (5888176946807).

21221533514425 is a wasteful number, since it uses less digits than its factorization.

21221533514425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134878 (or 134873 counting only the distinct ones).

The product of its digits is 288000, while the sum is 40.

The spelling of 21221533514425 in words is "twenty-one trillion, two hundred twenty-one billion, five hundred thirty-three million, five hundred fourteen thousand, four hundred twenty-five".