20777738 has 4 divisors (see below), whose sum is σ = 31166610. Its totient is φ = 10388868.

The previous prime is 20777737. The next prime is 20777741. The reversal of 20777738 is 83777702.

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

It can be written as a sum of positive squares in only one way, i.e., 14341369 + 6436369 = 3787^2 + 2537^2 .

It is a super-3 number, since 3×20777738³ (a number of 23 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20777695 and 20777704.

It is not an unprimeable number, because it can be changed into a prime (20777737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5194433 + ... + 5194436.

Almost surely, 2^20777738 is an apocalyptic number.

20777738 is a deficient number, since it is larger than the sum of its proper divisors (10388872).

20777738 is a wasteful number, since it uses less digits than its factorization.

20777738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10388871.

The product of its (nonzero) digits is 115248, while the sum is 41.

The square root of 20777738 is about 4558.2604137982. The cubic root of 20777738 is about 274.9156237008.

The spelling of 20777738 in words is "twenty million, seven hundred seventy-seven thousand, seven hundred thirty-eight".