721655534652 has 96 divisors (see below), whose sum is σ = 1822564800000. Its totient is φ = 220926432000.

The previous prime is 721655534651. The next prime is 721655534653. The reversal of 721655534652 is 256435556127.

It is an interprime number because it is at equal distance from previous prime (721655534651) and next prime (721655534653).

It is a super-2 number, since 2×721655534652² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 721655534595 and 721655534604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721655534651) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38480974 + ... + 38499722.

It is an arithmetic number, because the mean of its divisors is an integer number (18985050000).

Almost surely, 2^721655534652 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 721655534652, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (911282400000).

721655534652 is an abundant number, since it is smaller than the sum of its proper divisors (1100909265348).

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

721655534652 is a wasteful number, since it uses less digits than its factorization.

721655534652 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20003 (or 20001 counting only the distinct ones).

The product of its digits is 7560000, while the sum is 51.

The spelling of 721655534652 in words is "seven hundred twenty-one billion, six hundred fifty-five million, five hundred thirty-four thousand, six hundred fifty-two".