671247720 has 576 divisors, whose sum is σ = 2774865600. Its totient is φ = 138977280.

The previous prime is 671247719. The next prime is 671247727. The reversal of 671247720 is 27742176.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (671247727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 11377051 + ... + 11377109.

It is an arithmetic number, because the mean of its divisors is an integer number (4817475).

Almost surely, 2^671247720 is an apocalyptic number.

671247720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 671247720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1387432800).

671247720 is an abundant number, since it is smaller than the sum of its proper divisors (2103617880).

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

671247720 is a wasteful number, since it uses less digits than its factorization.

671247720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130 (or 110 counting only the distinct ones).

The product of its (nonzero) digits is 32928, while the sum is 36.

The square root of 671247720 is about 25908.4488150101. The cubic root of 671247720 is about 875.5768582525.

Adding to 671247720 its reverse (27742176), we get a palindrome (698989896).

The spelling of 671247720 in words is "six hundred seventy-one million, two hundred forty-seven thousand, seven hundred twenty".