20977903 has 4 divisors (see below), whose sum is σ = 20992608. Its totient is φ = 20963200.

The previous prime is 20977889. The next prime is 20977951. The reversal of 20977903 is 30977902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30977902 = 2 ⋅15488951.

It is a cyclic number.

It is not a de Polignac number, because 20977903 - 2⁵ = 20977871 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 (20977703) 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 in 3 ways as a sum of consecutive naturals, for example, 4951 + ... + 8152.

It is an arithmetic number, because the mean of its divisors is an integer number (5248152).

Almost surely, 2^20977903 is an apocalyptic number.

20977903 is a deficient number, since it is larger than the sum of its proper divisors (14705).

20977903 is a wasteful number, since it uses less digits than its factorization.

20977903 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14704.

The product of its (nonzero) digits is 23814, while the sum is 37.

The square root of 20977903 is about 4580.1640800303. The cubic root of 20977903 is about 275.7956155065.

Subtracting 20977903 from its reverse (30977902), we obtain a palindrome (9999999).

It can be divided in two parts, 2097 and 7903, that added together give a 4-th power (10000 = 10⁴).

The spelling of 20977903 in words is "twenty million, nine hundred seventy-seven thousand, nine hundred three".