20977144 has 8 divisors (see below), whose sum is σ = 39332160. Its totient is φ = 10488568.

The previous prime is 20977139. The next prime is 20977153. The reversal of 20977144 is 44177902.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1311064 + ... + 1311079.

It is an arithmetic number, because the mean of its divisors is an integer number (4916520).

Almost surely, 2^20977144 is an apocalyptic number.

It is an amenable number.

20977144 is a deficient number, since it is larger than the sum of its proper divisors (18355016).

20977144 is a wasteful number, since it uses less digits than its factorization.

20977144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2622149 (or 2622145 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 34.

The square root of 20977144 is about 4580.0812219872. The cubic root of 20977144 is about 275.7922892860.

The spelling of 20977144 in words is "twenty million, nine hundred seventy-seven thousand, one hundred forty-four".