20478958 has 4 divisors (see below), whose sum is σ = 30718440. Its totient is φ = 10239478.

The previous prime is 20478949. The next prime is 20478961. The reversal of 20478958 is 85987402.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 85987402 = 2 ⋅42993701.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5119738 + ... + 5119741.

It is an arithmetic number, because the mean of its divisors is an integer number (7679610).

Almost surely, 2^20478958 is an apocalyptic number.

20478958 is a deficient number, since it is larger than the sum of its proper divisors (10239482).

20478958 is a wasteful number, since it uses less digits than its factorization.

20478958 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10239481.

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 20478958 is about 4525.3682723067. The cubic root of 20478958 is about 273.5915112986.

The spelling of 20478958 in words is "twenty million, four hundred seventy-eight thousand, nine hundred fifty-eight".