20930971 has 4 divisors (see below), whose sum is σ = 21196000. Its totient is φ = 20665944.

The previous prime is 20930969. The next prime is 20930999. The reversal of 20930971 is 17903902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20930971 - 2¹ = 20930969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20930171) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 132396 + ... + 132553.

It is an arithmetic number, because the mean of its divisors is an integer number (5299000).

Almost surely, 2^20930971 is an apocalyptic number.

20930971 is a deficient number, since it is larger than the sum of its proper divisors (265029).

20930971 is an equidigital number, since it uses as much as digits as its factorization.

20930971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265028.

The product of its (nonzero) digits is 3402, while the sum is 31.

The square root of 20930971 is about 4575.0378140514. The cubic root of 20930971 is about 275.5897909238.

The spelling of 20930971 in words is "twenty million, nine hundred thirty thousand, nine hundred seventy-one".