20945377567 has 4 divisors (see below), whose sum is σ = 22047765880. Its totient is φ = 19842989256.

The previous prime is 20945377553. The next prime is 20945377573. The reversal of 20945377567 is 76577354902.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20945377567 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 (20945377517) 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, 551194128 + ... + 551194165.

It is an arithmetic number, because the mean of its divisors is an integer number (5511941470).

Almost surely, 2^20945377567 is an apocalyptic number.

20945377567 is a deficient number, since it is larger than the sum of its proper divisors (1102388313).

20945377567 is a wasteful number, since it uses less digits than its factorization.

20945377567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1102388312.

The product of its (nonzero) digits is 11113200, while the sum is 55.

The spelling of 20945377567 in words is "twenty billion, nine hundred forty-five million, three hundred seventy-seven thousand, five hundred sixty-seven".