20966947 has 4 divisors (see below), whose sum is σ = 20976280. Its totient is φ = 20957616.

The previous prime is 20966923. The next prime is 20966951. The reversal of 20966947 is 74966902.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20966947 - 2¹⁹ = 20442659 is a prime.

It is a super-2 number, since 2×20966947² = 879225733001618, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20966147) 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, 988 + ... + 6550.

It is an arithmetic number, because the mean of its divisors is an integer number (5244070).

Almost surely, 2^20966947 is an apocalyptic number.

20966947 is a deficient number, since it is larger than the sum of its proper divisors (9333).

20966947 is an equidigital number, since it uses as much as digits as its factorization.

20966947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9332.

The product of its (nonzero) digits is 163296, while the sum is 43.

The square root of 20966947 is about 4578.9678968082. The cubic root of 20966947 is about 275.7475944540.

The spelling of 20966947 in words is "twenty million, nine hundred sixty-six thousand, nine hundred forty-seven".