20405173450 has 12 divisors (see below), whose sum is σ = 37953622710. Its totient is φ = 8162069360.

The previous prime is 20405173447. The next prime is 20405173463. The reversal of 20405173450 is 5437150402.

It can be written as a sum of positive squares in 3 ways, for example, as 13569687121 + 6835486329 = 116489^2 + 82677^2 .

It is a super-2 number, since 2×20405173450² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 204051685 + ... + 204051784.

Almost surely, 2^20405173450 is an apocalyptic number.

20405173450 is a deficient number, since it is larger than the sum of its proper divisors (17548449260).

20405173450 is a wasteful number, since it uses less digits than its factorization.

20405173450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408103481 (or 408103476 counting only the distinct ones).

The product of its (nonzero) digits is 16800, while the sum is 31.

The spelling of 20405173450 in words is "twenty billion, four hundred five million, one hundred seventy-three thousand, four hundred fifty".