21246017420 has 12 divisors (see below), whose sum is σ = 44616636624. Its totient is φ = 8498406960.

The previous prime is 21246017411. The next prime is 21246017423. The reversal of 21246017420 is 2471064212.

It is not an unprimeable number, because it can be changed into a prime (21246017423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 531150416 + ... + 531150455.

It is an arithmetic number, because the mean of its divisors is an integer number (3718053052).

Almost surely, 2^21246017420 is an apocalyptic number.

21246017420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21246017420 is an abundant number, since it is smaller than the sum of its proper divisors (23370619204).

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

21246017420 is a wasteful number, since it uses less digits than its factorization.

21246017420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1062300880 (or 1062300878 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 29.

The spelling of 21246017420 in words is "twenty-one billion, two hundred forty-six million, seventeen thousand, four hundred twenty".