20955973 has 2 divisors, whose sum is σ = 20955974. Its totient is φ = 20955972.

The previous prime is 20955971. The next prime is 20955989. The reversal of 20955973 is 37955902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19909444 + 1046529 = 4462^2 + 1023^2 .

It is a cyclic number.

It is not a de Polignac number, because 20955973 - 2¹ = 20955971 is a prime.

Together with 20955971, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20955971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10477986 + 10477987.

It is an arithmetic number, because the mean of its divisors is an integer number (10477987).

Almost surely, 2^20955973 is an apocalyptic number.

It is an amenable number.

20955973 is a deficient number, since it is larger than the sum of its proper divisors (1).

20955973 is an equidigital number, since it uses as much as digits as its factorization.

20955973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 85050, while the sum is 40.

The square root of 20955973 is about 4577.7694349978. The cubic root of 20955973 is about 275.6994777334.

The spelling of 20955973 in words is "twenty million, nine hundred fifty-five thousand, nine hundred seventy-three".