21373617265040 has 20 divisors (see below), whose sum is σ = 49693660141404. Its totient is φ = 8549446905984.

The previous prime is 21373617265031. The next prime is 21373617265057. The reversal of 21373617265040 is 4056271637312.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 5015378166016 + 16358239099024 = 2239504^2 + 4044532^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133585107827 + ... + 133585107986.

Almost surely, 2^{21373617265040} is an apocalyptic number.

21373617265040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21373617265040 is an abundant number, since it is smaller than the sum of its proper divisors (28320042876364).

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

21373617265040 is a wasteful number, since it uses less digits than its factorization.

21373617265040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267170215826 (or 267170215820 counting only the distinct ones).

The product of its (nonzero) digits is 1270080, while the sum is 47.

The spelling of 21373617265040 in words is "twenty-one trillion, three hundred seventy-three billion, six hundred seventeen million, two hundred sixty-five thousand, forty".