20409624178 has 4 divisors (see below), whose sum is σ = 30614436270. Its totient is φ = 10204812088.

The previous prime is 20409624127. The next prime is 20409624203. The reversal of 20409624178 is 87142690402.

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., 19463877169 + 945747009 = 139513^2 + 30753^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5102406043 + ... + 5102406046.

Almost surely, 2^20409624178 is an apocalyptic number.

20409624178 is a deficient number, since it is larger than the sum of its proper divisors (10204812092).

20409624178 is a wasteful number, since it uses less digits than its factorization.

20409624178 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10204812091.

The product of its (nonzero) digits is 193536, while the sum is 43.

The spelling of 20409624178 in words is "twenty billion, four hundred nine million, six hundred twenty-four thousand, one hundred seventy-eight".