21661351025352 has 32 divisors (see below), whose sum is σ = 54153772630080. Its totient is φ = 7220397666240.

The previous prime is 21661351025291. The next prime is 21661351025359. The reversal of 21661351025352 is 25352015316612.

It is not an unprimeable number, because it can be changed into a prime (21661351025359) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 139077 + ... + 6583467.

It is an arithmetic number, because the mean of its divisors is an integer number (1692305394690).

Almost surely, 2^{21661351025352} is an apocalyptic number.

It is an amenable number.

21661351025352 is an abundant number, since it is smaller than the sum of its proper divisors (32492421604728).

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

21661351025352 is a wasteful number, since it uses less digits than its factorization.

21661351025352 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6584453 (or 6584449 counting only the distinct ones).

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

The spelling of 21661351025352 in words is "twenty-one trillion, six hundred sixty-one billion, three hundred fifty-one million, twenty-five thousand, three hundred fifty-two".