19970725809 has 8 divisors (see below), whose sum is σ = 28193965920. Its totient is φ = 12530651456.

The previous prime is 19970725807. The next prime is 19970725811. The reversal of 19970725809 is 90852707991.

It is an interprime number because it is at equal distance from previous prime (19970725807) and next prime (19970725811).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19970725809 - 2¹ = 19970725807 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19970725807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 195791379 + ... + 195791480.

It is an arithmetic number, because the mean of its divisors is an integer number (3524245740).

Almost surely, 2^19970725809 is an apocalyptic number.

It is an amenable number.

19970725809 is a deficient number, since it is larger than the sum of its proper divisors (8223240111).

19970725809 is a wasteful number, since it uses less digits than its factorization.

19970725809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391582879.

The product of its (nonzero) digits is 2857680, while the sum is 57.

The spelling of 19970725809 in words is "nineteen billion, nine hundred seventy million, seven hundred twenty-five thousand, eight hundred nine".