12720867869638 has 4 divisors (see below), whose sum is σ = 19081301804460. Its totient is φ = 6360433934818.

The previous prime is 12720867869623. The next prime is 12720867869657. The reversal of 12720867869638 is 83696876802721.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3180216967408 + ... + 3180216967411.

It is an arithmetic number, because the mean of its divisors is an integer number (4770325451115).

Almost surely, 2^{12720867869638} is an apocalyptic number.

12720867869638 is a deficient number, since it is larger than the sum of its proper divisors (6360433934822).

12720867869638 is an equidigital number, since it uses as much as digits as its factorization.

12720867869638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6360433934821.

The product of its (nonzero) digits is 585252864, while the sum is 73.

The spelling of 12720867869638 in words is "twelve trillion, seven hundred twenty billion, eight hundred sixty-seven million, eight hundred sixty-nine thousand, six hundred thirty-eight".