19970636638 has 8 divisors (see below), whose sum is σ = 30129111288. Its totient is φ = 9927599544.

The previous prime is 19970636591. The next prime is 19970636687. The reversal of 19970636638 is 83663607991.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28858956 + ... + 28859647.

It is an arithmetic number, because the mean of its divisors is an integer number (3766138911).

Almost surely, 2^19970636638 is an apocalyptic number.

19970636638 is a deficient number, since it is larger than the sum of its proper divisors (10158474650).

19970636638 is a wasteful number, since it uses less digits than its factorization.

19970636638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57718778.

The product of its (nonzero) digits is 8817984, while the sum is 58.

The spelling of 19970636638 in words is "nineteen billion, nine hundred seventy million, six hundred thirty-six thousand, six hundred thirty-eight".