20963842 has 4 divisors (see below), whose sum is σ = 31445766. Its totient is φ = 10481920.

The previous prime is 20963837. The next prime is 20963849. The reversal of 20963842 is 24836902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24836902 = 2 ⋅12418451.

It can be written as a sum of positive squares in only one way, i.e., 14907321 + 6056521 = 3861^2 + 2461^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20963798 and 20963807.

It is not an unprimeable number, because it can be changed into a prime (20963849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5240959 + ... + 5240962.

Almost surely, 2^20963842 is an apocalyptic number.

20963842 is a deficient number, since it is larger than the sum of its proper divisors (10481924).

20963842 is a wasteful number, since it uses less digits than its factorization.

20963842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10481923.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 20963842 is about 4578.6288340506. The cubic root of 20963842 is about 275.7339819405.

The spelling of 20963842 in words is "twenty million, nine hundred sixty-three thousand, eight hundred forty-two".