20951923 has 2 divisors, whose sum is σ = 20951924. Its totient is φ = 20951922.

The previous prime is 20951921. The next prime is 20951947. The reversal of 20951923 is 32915902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20951923 - 2¹ = 20951921 is a prime.

It is a super-3 number, since 3×20951923³ (a number of 23 digits) contains 333 as substring.

Together with 20951921, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20951921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10475961 + 10475962.

It is an arithmetic number, because the mean of its divisors is an integer number (10475962).

Almost surely, 2^20951923 is an apocalyptic number.

20951923 is a deficient number, since it is larger than the sum of its proper divisors (1).

20951923 is an equidigital number, since it uses as much as digits as its factorization.

20951923 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4860, while the sum is 31.

The square root of 20951923 is about 4577.3270584480. The cubic root of 20951923 is about 275.6817158154.

The spelling of 20951923 in words is "twenty million, nine hundred fifty-one thousand, nine hundred twenty-three".