20965642 has 4 divisors (see below), whose sum is σ = 31448466. Its totient is φ = 10482820.

The previous prime is 20965621. The next prime is 20965649. The reversal of 20965642 is 24656902.

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

It can be written as a sum of positive squares in only one way, i.e., 16475481 + 4490161 = 4059^2 + 2119^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20965598 and 20965607.

It is not an unprimeable number, because it can be changed into a prime (20965649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5241409 + ... + 5241412.

Almost surely, 2^20965642 is an apocalyptic number.

20965642 is a deficient number, since it is larger than the sum of its proper divisors (10482824).

20965642 is a wasteful number, since it uses less digits than its factorization.

20965642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10482823.

The product of its (nonzero) digits is 25920, while the sum is 34.

The square root of 20965642 is about 4578.8253952297. The cubic root of 20965642 is about 275.7418734164.

The spelling of 20965642 in words is "twenty million, nine hundred sixty-five thousand, six hundred forty-two".