21620541355 has 8 divisors (see below), whose sum is σ = 29651028192. Its totient is φ = 14825514048.

The previous prime is 21620541337. The next prime is 21620541403. The reversal of 21620541355 is 55314502612.

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

It is a cyclic number.

It is not a de Polignac number, because 21620541355 - 2¹⁷ = 21620410283 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21620541355.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 308864842 + ... + 308864911.

It is an arithmetic number, because the mean of its divisors is an integer number (3706378524).

Almost surely, 2^21620541355 is an apocalyptic number.

21620541355 is a deficient number, since it is larger than the sum of its proper divisors (8030486837).

21620541355 is an equidigital number, since it uses as much as digits as its factorization.

21620541355 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 617729765.

The product of its (nonzero) digits is 36000, while the sum is 34.

The spelling of 21620541355 in words is "twenty-one billion, six hundred twenty million, five hundred forty-one thousand, three hundred fifty-five".