20780767 has 4 divisors (see below), whose sum is σ = 23749456. Its totient is φ = 17812080.

The previous prime is 20780761. The next prime is 20780779. The reversal of 20780767 is 76708702.

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 20780767 - 2³ = 20780759 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 (20780761) 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, 1484334 + ... + 1484347.

It is an arithmetic number, because the mean of its divisors is an integer number (5937364).

Almost surely, 2^20780767 is an apocalyptic number.

20780767 is a deficient number, since it is larger than the sum of its proper divisors (2968689).

20780767 is an equidigital number, since it uses as much as digits as its factorization.

20780767 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2968688.

The product of its (nonzero) digits is 32928, while the sum is 37.

The square root of 20780767 is about 4558.5926556340. The cubic root of 20780767 is about 274.9289822124.

The spelling of 20780767 in words is "twenty million, seven hundred eighty thousand, seven hundred sixty-seven".