20787077 has 4 divisors (see below), whose sum is σ = 21179340. Its totient is φ = 20394816.

The previous prime is 20787061. The next prime is 20787079. The reversal of 20787077 is 77078702.

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

It can be written as a sum of positive squares in 2 ways, for example, as 12208036 + 8579041 = 3494^2 + 2929^2 .

It is a cyclic number.

It is not a de Polignac number, because 20787077 - 2⁴ = 20787061 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20787077.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20787079) 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, 196052 + ... + 196157.

It is an arithmetic number, because the mean of its divisors is an integer number (5294835).

Almost surely, 2^20787077 is an apocalyptic number.

It is an amenable number.

20787077 is a deficient number, since it is larger than the sum of its proper divisors (392263).

20787077 is an equidigital number, since it uses as much as digits as its factorization.

20787077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392262.

The product of its (nonzero) digits is 38416, while the sum is 38.

The square root of 20787077 is about 4559.2847026699. The cubic root of 20787077 is about 274.9568064392.

The spelling of 20787077 in words is "twenty million, seven hundred eighty-seven thousand, seventy-seven".