20403765549 has 6 divisors (see below), whose sum is σ = 29472105806. Its totient is φ = 13602510360.

The previous prime is 20403765541. The next prime is 20403765553. The reversal of 20403765549 is 94556730402.

20403765549 is a `hidden beast` number, since 2 + 0 + 40 + 3 + 7 + 65 + 549 = 666.

It can be written as a sum of positive squares in only one way, i.e., 17766224100 + 2637541449 = 133290^2 + 51357^2 .

It is not a de Polignac number, because 20403765549 - 2³ = 20403765541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20403765541) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1133542522 + ... + 1133542539.

Almost surely, 2^20403765549 is an apocalyptic number.

It is an amenable number.

20403765549 is a deficient number, since it is larger than the sum of its proper divisors (9068340257).

20403765549 is a wasteful number, since it uses less digits than its factorization.

20403765549 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2267085067 (or 2267085064 counting only the distinct ones).

The product of its (nonzero) digits is 907200, while the sum is 45.

The spelling of 20403765549 in words is "twenty billion, four hundred three million, seven hundred sixty-five thousand, five hundred forty-nine".