135521320020 has 24 divisors (see below), whose sum is σ = 379459696224. Its totient is φ = 36139018656.

The previous prime is 135521319979. The next prime is 135521320063. The reversal of 135521320020 is 20023125531.

It is a happy number.

135521320020 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

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, 1129344274 + ... + 1129344393.

It is an arithmetic number, because the mean of its divisors is an integer number (15810820676).

Almost surely, 2^135521320020 is an apocalyptic number.

135521320020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

135521320020 is an abundant number, since it is smaller than the sum of its proper divisors (243938376204).

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

135521320020 is a wasteful number, since it uses less digits than its factorization.

135521320020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2258688679 (or 2258688677 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

Adding to 135521320020 its reverse (20023125531), we get a palindrome (155544445551).

The spelling of 135521320020 in words is "one hundred thirty-five billion, five hundred twenty-one million, three hundred twenty thousand, twenty".