21240570408 has 32 divisors (see below), whose sum is σ = 53106580800. Its totient is φ = 7079502848.

The previous prime is 21240570347. The next prime is 21240570409. The reversal of 21240570408 is 80407504212.

It is a super-3 number, since 3×21240570408³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21240570409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 250285 + ... + 324227.

It is an arithmetic number, because the mean of its divisors is an integer number (1659580650).

Almost surely, 2^21240570408 is an apocalyptic number.

It is an amenable number.

21240570408 is an abundant number, since it is smaller than the sum of its proper divisors (31866010392).

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

21240570408 is a wasteful number, since it uses less digits than its factorization.

21240570408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85921 (or 85917 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 33.

The spelling of 21240570408 in words is "twenty-one billion, two hundred forty million, five hundred seventy thousand, four hundred eight".