721412565420 has 192 divisors, whose sum is σ = 2153588363136. Its totient is φ = 179809812480.

The previous prime is 721412565409. The next prime is 721412565421. The reversal of 721412565420 is 24565214127.

It is not an unprimeable number, because it can be changed into a prime (721412565421) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 126184402 + ... + 126190118.

It is an arithmetic number, because the mean of its divisors is an integer number (11216606058).

Almost surely, 2^721412565420 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 721412565420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1076794181568).

721412565420 is an abundant number, since it is smaller than the sum of its proper divisors (1432175797716).

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

721412565420 is a wasteful number, since it uses less digits than its factorization.

721412565420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6580 (or 6578 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 39.

Adding to 721412565420 its reverse (24565214127), we get a palindrome (745977779547).

The spelling of 721412565420 in words is "seven hundred twenty-one billion, four hundred twelve million, five hundred sixty-five thousand, four hundred twenty".