20509157450 has 24 divisors (see below), whose sum is σ = 39034177248. Its totient is φ = 8012879280.

The previous prime is 20509157447. The next prime is 20509157587. The reversal of 20509157450 is 5475190502.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4767422 + ... + 4771721.

It is an arithmetic number, because the mean of its divisors is an integer number (1626424052).

Almost surely, 2^20509157450 is an apocalyptic number.

20509157450 is a deficient number, since it is larger than the sum of its proper divisors (18525019798).

20509157450 is a wasteful number, since it uses less digits than its factorization.

20509157450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9539198 (or 9539193 counting only the distinct ones).

The product of its (nonzero) digits is 63000, while the sum is 38.

The spelling of 20509157450 in words is "twenty billion, five hundred nine million, one hundred fifty-seven thousand, four hundred fifty".