66431000 has 32 divisors (see below), whose sum is σ = 155450880. Its totient is φ = 26572000.

The previous prime is 66430997. The next prime is 66431003. The reversal of 66431000 is 13466.

66431000 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (66430997) and next prime (66431003).

It is a super-2 number, since 2×66431000² = 8826155522000000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66431003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32216 + ... + 34215.

It is an arithmetic number, because the mean of its divisors is an integer number (4857840).

Almost surely, 2^66431000 is an apocalyptic number.

It is an amenable number.

66431000 is an abundant number, since it is smaller than the sum of its proper divisors (89019880).

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

66431000 is a wasteful number, since it uses less digits than its factorization.

66431000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66452 (or 66438 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 66431000 is about 8150.5214557107. The cubic root of 66431000 is about 405.0017781764.

Adding to 66431000 its reverse (13466), we get a palindrome (66444466).

The spelling of 66431000 in words is "sixty-six million, four hundred thirty-one thousand".