20976139 has 2 divisors, whose sum is σ = 20976140. Its totient is φ = 20976138.

The previous prime is 20976127. The next prime is 20976167. The reversal of 20976139 is 93167902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20976139 - 2⁵ = 20976107 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20976098 and 20976107.

It is not a weakly prime, because it can be changed into another prime (20976539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10488069 + 10488070.

It is an arithmetic number, because the mean of its divisors is an integer number (10488070).

Almost surely, 2^20976139 is an apocalyptic number.

20976139 is a deficient number, since it is larger than the sum of its proper divisors (1).

20976139 is an equidigital number, since it uses as much as digits as its factorization.

20976139 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20412, while the sum is 37.

The square root of 20976139 is about 4579.9715064616. The cubic root of 20976139 is about 275.7878848784.

It can be divided in two parts, 20976 and 139, that added together give a triangular number (21115 = T₂₀₅).

The spelling of 20976139 in words is "twenty million, nine hundred seventy-six thousand, one hundred thirty-nine".