19970397397 has 4 divisors (see below), whose sum is σ = 20659031820. Its totient is φ = 19281762976.

The previous prime is 19970397371. The next prime is 19970397451. The reversal of 19970397397 is 79379307991.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11957641201 + 8012756196 = 109351^2 + 89514^2 .

It is a cyclic number.

It is not a de Polignac number, because 19970397397 - 2²³ = 19962008789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19970397367) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 344317168 + ... + 344317225.

It is an arithmetic number, because the mean of its divisors is an integer number (5164757955).

Almost surely, 2^19970397397 is an apocalyptic number.

It is an amenable number.

19970397397 is a deficient number, since it is larger than the sum of its proper divisors (688634423).

19970397397 is an equidigital number, since it uses as much as digits as its factorization.

19970397397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688634422.

The product of its (nonzero) digits is 20253807, while the sum is 64.

The spelling of 19970397397 in words is "nineteen billion, nine hundred seventy million, three hundred ninety-seven thousand, three hundred ninety-seven".