20605723400 has 24 divisors (see below), whose sum is σ = 47908307370. Its totient is φ = 8242289280.

The previous prime is 20605723399. The next prime is 20605723417. The reversal of 20605723400 is 432750602.

It can be written as a sum of positive squares in 3 ways, for example, as 15286355044 + 5319368356 = 123638^2 + 72934^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 51514109 + ... + 51514508.

Almost surely, 2^20605723400 is an apocalyptic number.

20605723400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20605723400 is an abundant number, since it is smaller than the sum of its proper divisors (27302583970).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20605723400 is a wasteful number, since it uses less digits than its factorization.

20605723400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103028633 (or 103028624 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 29.

The spelling of 20605723400 in words is "twenty billion, six hundred five million, seven hundred twenty-three thousand, four hundred".