20185451138 has 8 divisors (see below), whose sum is σ = 30278951820. Its totient is φ = 10092467200.

The previous prime is 20185451137. The next prime is 20185451141. The reversal of 20185451138 is 83115458102.

It can be written as a sum of positive squares in 2 ways, for example, as 19791706489 + 393744649 = 140683^2 + 19843^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (20185451137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9263 + ... + 201138.

Almost surely, 2^20185451138 is an apocalyptic number.

20185451138 is a deficient number, since it is larger than the sum of its proper divisors (10093500682).

20185451138 is a wasteful number, since it uses less digits than its factorization.

20185451138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258372.

The product of its (nonzero) digits is 38400, while the sum is 38.

The spelling of 20185451138 in words is "twenty billion, one hundred eighty-five million, four hundred fifty-one thousand, one hundred thirty-eight".