97721260816 has 45 divisors (see below), whose sum is σ = 195717175029. Its totient is φ = 47265724800.

The previous prime is 97721260801. The next prime is 97721260817. The reversal of 97721260816 is 61806212779.

The square root of 97721260816 is 312604.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 77510416 + 97643750400 = 8804^2 + 312480^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 97721260816.

It is not an unprimeable number, because it can be changed into a prime (97721260817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 38761636 + ... + 38764156.

Almost surely, 2^97721260816 is an apocalyptic number.

97721260816 is the 312604-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 97721260816

97721260816 is an abundant number, since it is smaller than the sum of its proper divisors (97995914213).

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

97721260816 is an frugal number, since it uses more digits than its factorization.

97721260816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5112 (or 2554 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 49.

Multiplying 97721260816 by its sum of digits (49), we get a square (4788341779984 = 2188228²).

The spelling of 97721260816 in words is "ninety-seven billion, seven hundred twenty-one million, two hundred sixty thousand, eight hundred sixteen".