66600404 has 24 divisors (see below), whose sum is σ = 125911968. Its totient is φ = 30641760.

The previous prime is 66600379. The next prime is 66600409. The reversal of 66600404 is 40400666.

It is a super-2 number, since 2×66600404² = 8871227625926432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66600409) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16199 + ... + 19889.

It is an arithmetic number, because the mean of its divisors is an integer number (5246332).

Almost surely, 2^66600404 is an apocalyptic number.

It is an amenable number.

66600404 is a deficient number, since it is larger than the sum of its proper divisors (59311564).

66600404 is a wasteful number, since it uses less digits than its factorization.

66600404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4055 (or 4053 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 66600404 is about 8160.9070574293. The cubic root of 66600404 is about 405.3457475302.

The spelling of 66600404 in words is "sixty-six million, six hundred thousand, four hundred four".