20756977 has 2 divisors, whose sum is σ = 20756978. Its totient is φ = 20756976.

The previous prime is 20756969. The next prime is 20756993. The reversal of 20756977 is 77965702.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14561856 + 6195121 = 3816^2 + 2489^2 .

It is a cyclic number.

It is not a de Polignac number, because 20756977 - 2³ = 20756969 is a prime.

It is not a weakly prime, because it can be changed into another prime (20756777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10378488 + 10378489.

It is an arithmetic number, because the mean of its divisors is an integer number (10378489).

Almost surely, 2^20756977 is an apocalyptic number.

It is an amenable number.

20756977 is a deficient number, since it is larger than the sum of its proper divisors (1).

20756977 is an equidigital number, since it uses as much as digits as its factorization.

20756977 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 185220, while the sum is 43.

The square root of 20756977 is about 4555.9825504495. The cubic root of 20756977 is about 274.8240284673.

The spelling of 20756977 in words is "twenty million, seven hundred fifty-six thousand, nine hundred seventy-seven".