21550708355 has 8 divisors (see below), whose sum is σ = 28211836464. Its totient is φ = 15673242400.

The previous prime is 21550708343. The next prime is 21550708357. The reversal of 21550708355 is 55380705512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21550708355 - 2⁸ = 21550708099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21550708357) 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, 195915476 + ... + 195915585.

It is an arithmetic number, because the mean of its divisors is an integer number (3526479558).

Almost surely, 2^21550708355 is an apocalyptic number.

21550708355 is a deficient number, since it is larger than the sum of its proper divisors (6661128109).

21550708355 is a wasteful number, since it uses less digits than its factorization.

21550708355 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391831077.

The product of its (nonzero) digits is 210000, while the sum is 41.

The spelling of 21550708355 in words is "twenty-one billion, five hundred fifty million, seven hundred eight thousand, three hundred fifty-five".