21420000340 has 48 divisors (see below), whose sum is σ = 48003121152. Its totient is φ = 8000487936.

The previous prime is 21420000337. The next prime is 21420000347. The reversal of 21420000340 is 4300002412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21420000347) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 204852 + ... + 291211.

It is an arithmetic number, because the mean of its divisors is an integer number (1000065024).

Almost surely, 2^21420000340 is an apocalyptic number.

21420000340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21420000340 is an abundant number, since it is smaller than the sum of its proper divisors (26583120812).

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

21420000340 is a wasteful number, since it uses less digits than its factorization.

21420000340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 496216 (or 496214 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

Adding to 21420000340 its reverse (4300002412), we get a palindrome (25720002752).

The spelling of 21420000340 in words is "twenty-one billion, four hundred twenty million, three hundred forty", and thus it is an aban number.