20977877 has 8 divisors (see below), whose sum is σ = 21449016. Its totient is φ = 20509632.

The previous prime is 20977871. The next prime is 20977889. The reversal of 20977877 is 77877902.

It can be written as a sum of positive squares in 4 ways, for example, as 10699441 + 10278436 = 3271^2 + 3206^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20977877 - 2⁴ = 20977861 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 (20977871) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20543 + ... + 21539.

It is an arithmetic number, because the mean of its divisors is an integer number (2681127).

Almost surely, 2^20977877 is an apocalyptic number.

It is an amenable number.

20977877 is a deficient number, since it is larger than the sum of its proper divisors (471139).

20977877 is an equidigital number, since it uses as much as digits as its factorization.

20977877 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1447.

The product of its (nonzero) digits is 345744, while the sum is 47.

The square root of 20977877 is about 4580.1612417032. The cubic root of 20977877 is about 275.7955015662.

The spelling of 20977877 in words is "twenty million, nine hundred seventy-seven thousand, eight hundred seventy-seven".