721253649375 has 320 divisors, whose sum is σ = 1594349644800. Its totient is φ = 315254592000.

The previous prime is 721253649359. The next prime is 721253649377. The reversal of 721253649375 is 573946352127.

721253649375 is a `hidden beast` number, since 7 + 2 + 12 + 536 + 4 + 93 + 7 + 5 = 666.

It is not a de Polignac number, because 721253649375 - 2⁴ = 721253649359 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721253649377) by changing a digit.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 257865477 + ... + 257868273.

It is an arithmetic number, because the mean of its divisors is an integer number (4982342640).

Almost surely, 2^721253649375 is an apocalyptic number.

721253649375 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

721253649375 is an abundant number, since it is smaller than the sum of its proper divisors (873095995425).

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

721253649375 is a wasteful number, since it uses less digits than its factorization.

721253649375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2929 (or 2908 counting only the distinct ones).

The product of its digits is 9525600, while the sum is 54.

The spelling of 721253649375 in words is "seven hundred twenty-one billion, two hundred fifty-three million, six hundred forty-nine thousand, three hundred seventy-five".