21202512340 has 24 divisors (see below), whose sum is σ = 44845607520. Its totient is φ = 8419989408.

The previous prime is 21202512337. The next prime is 21202512367. The reversal of 21202512340 is 4321520212.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3810622 + ... + 3816181.

It is an arithmetic number, because the mean of its divisors is an integer number (1868566980).

Almost surely, 2^21202512340 is an apocalyptic number.

21202512340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21202512340 is an abundant number, since it is smaller than the sum of its proper divisors (23643095180).

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

21202512340 is a wasteful number, since it uses less digits than its factorization.

21202512340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7626951 (or 7626949 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The spelling of 21202512340 in words is "twenty-one billion, two hundred two million, five hundred twelve thousand, three hundred forty".