21205890490308 has 48 divisors (see below), whose sum is σ = 50432025942144. Its totient is φ = 6933695937280.

The previous prime is 21205890490297. The next prime is 21205890490361. The reversal of 21205890490308 is 80309409850212.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63003585 + ... + 63339272.

It is an arithmetic number, because the mean of its divisors is an integer number (1050667207128).

Almost surely, 2^{21205890490308} is an apocalyptic number.

It is an amenable number.

21205890490308 is an abundant number, since it is smaller than the sum of its proper divisors (29226135451836).

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

21205890490308 is a wasteful number, since it uses less digits than its factorization.

21205890490308 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126343132 (or 126343130 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 51.

The spelling of 21205890490308 in words is "twenty-one trillion, two hundred five billion, eight hundred ninety million, four hundred ninety thousand, three hundred eight".