21213554606440 has 64 divisors (see below), whose sum is σ = 57757913395200. Its totient is φ = 6845382325248.

The previous prime is 21213554606407. The next prime is 21213554606459. The reversal of 21213554606440 is 4460645531212.

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, 2228309800 + ... + 2228319319.

It is an arithmetic number, because the mean of its divisors is an integer number (902467396800).

Almost surely, 2^{21213554606440} is an apocalyptic number.

21213554606440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21213554606440 is an abundant number, since it is smaller than the sum of its proper divisors (36544358788760).

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

21213554606440 is a wasteful number, since it uses less digits than its factorization.

21213554606440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4456629154 (or 4456629150 counting only the distinct ones).

The product of its (nonzero) digits is 691200, while the sum is 43.

The spelling of 21213554606440 in words is "twenty-one trillion, two hundred thirteen billion, five hundred fifty-four million, six hundred six thousand, four hundred forty".