197894430721 has 16 divisors (see below), whose sum is σ = 213861186000. Its totient is φ = 182034892800.

The previous prime is 197894430719. The next prime is 197894430733. The reversal of 197894430721 is 127034498791.

It can be written as a sum of positive squares in 8 ways, for example, as 10128208321 + 187766222400 = 100639^2 + 433320^2 .

It is a cyclic number.

It is not a de Polignac number, because 197894430721 - 2¹ = 197894430719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (197894430791) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5366655 + ... + 5403403.

It is an arithmetic number, because the mean of its divisors is an integer number (13366324125).

Almost surely, 2^197894430721 is an apocalyptic number.

It is an amenable number.

197894430721 is a deficient number, since it is larger than the sum of its proper divisors (15966755279).

197894430721 is a wasteful number, since it uses less digits than its factorization.

197894430721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38196.

The product of its (nonzero) digits is 3048192, while the sum is 55.

The spelling of 197894430721 in words is "one hundred ninety-seven billion, eight hundred ninety-four million, four hundred thirty thousand, seven hundred twenty-one".