66431428 has 24 divisors (see below), whose sum is σ = 136455872. Its totient is φ = 27700704.

The previous prime is 66431399. The next prime is 66431441. The reversal of 66431428 is 82413466.

It is a super-2 number, since 2×66431428² = 8826269252238368, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66431393 and 66431402.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31026 + ... + 33097.

Almost surely, 2^66431428 is an apocalyptic number.

It is an amenable number.

66431428 is an abundant number, since it is smaller than the sum of its proper divisors (70024444).

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

66431428 is a wasteful number, since it uses less digits than its factorization.

66431428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64171 (or 64169 counting only the distinct ones).

The product of its digits is 27648, while the sum is 34.

The square root of 66431428 is about 8150.5477116572. The cubic root of 66431428 is about 405.0026479530.

The spelling of 66431428 in words is "sixty-six million, four hundred thirty-one thousand, four hundred twenty-eight".