20702742667 has 4 divisors (see below), whose sum is σ = 20710531240. Its totient is φ = 20694954096.

The previous prime is 20702742659. The next prime is 20702742677. The reversal of 20702742667 is 76624720702.

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

It is a cyclic number.

It is not a de Polignac number, because 20702742667 - 2³ = 20702742659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20702742677) 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, 3890298 + ... + 3895615.

It is an arithmetic number, because the mean of its divisors is an integer number (5177632810).

Almost surely, 2^20702742667 is an apocalyptic number.

20702742667 is a deficient number, since it is larger than the sum of its proper divisors (7788573).

20702742667 is an equidigital number, since it uses as much as digits as its factorization.

20702742667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7788572.

The product of its (nonzero) digits is 395136, while the sum is 43.

The spelling of 20702742667 in words is "twenty billion, seven hundred two million, seven hundred forty-two thousand, six hundred sixty-seven".