21552395357 has 4 divisors (see below), whose sum is σ = 21959044380. Its totient is φ = 21145746336.

The previous prime is 21552395317. The next prime is 21552395411. The reversal of 21552395357 is 75359325512.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 19740531001 + 1811864356 = 140501^2 + 42566^2 .

It is a cyclic number.

It is not a de Polignac number, because 21552395357 - 2⁸ = 21552395101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21552395317) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 203324432 + ... + 203324537.

It is an arithmetic number, because the mean of its divisors is an integer number (5489761095).

Almost surely, 2^21552395357 is an apocalyptic number.

It is an amenable number.

21552395357 is a deficient number, since it is larger than the sum of its proper divisors (406649023).

21552395357 is an equidigital number, since it uses as much as digits as its factorization.

21552395357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406649022.

The product of its digits is 1417500, while the sum is 47.

The spelling of 21552395357 in words is "twenty-one billion, five hundred fifty-two million, three hundred ninety-five thousand, three hundred fifty-seven".