20487428 has 12 divisors (see below), whose sum is σ = 38611020. Its totient is φ = 9455712.

The previous prime is 20487407. The next prime is 20487433. The reversal of 20487428 is 82478402.

It can be written as a sum of positive squares in 2 ways, for example, as 12376324 + 8111104 = 3518^2 + 2848^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 196943 + ... + 197046.

It is an arithmetic number, because the mean of its divisors is an integer number (3217585).

Almost surely, 2^20487428 is an apocalyptic number.

It is an amenable number.

20487428 is a deficient number, since it is larger than the sum of its proper divisors (18123592).

20487428 is a wasteful number, since it uses less digits than its factorization.

20487428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 394006 (or 394004 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 35.

The square root of 20487428 is about 4526.3040110006. The cubic root of 20487428 is about 273.6292248173.

The spelling of 20487428 in words is "twenty million, four hundred eighty-seven thousand, four hundred twenty-eight".