66126400 has 84 divisors (see below), whose sum is σ = 167259508. Its totient is φ = 25712640.

The previous prime is 66126391. The next prime is 66126419. The reversal of 66126400 is 462166.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 2637376 + 63489024 = 1624^2 + 7968^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 58642 + ... + 59758.

Almost surely, 2^66126400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66126400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83629754).

66126400 is an abundant number, since it is smaller than the sum of its proper divisors (101133108).

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

66126400 is a wasteful number, since it uses less digits than its factorization.

66126400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1176 (or 1161 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 66126400 is about 8131.8140657543. The cubic root of 66126400 is about 404.3818237746.

Adding to 66126400 its reverse (462166), we get a palindrome (66588566).

The spelling of 66126400 in words is "sixty-six million, one hundred twenty-six thousand, four hundred".