55400666 has 4 divisors (see below), whose sum is σ = 83101002. Its totient is φ = 27700332.

The previous prime is 55400663. The next prime is 55400693. The reversal of 55400666 is 66600455.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 53655625 + 1745041 = 7325^2 + 1321^2 .

It is not an unprimeable number, because it can be changed into a prime (55400663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13850165 + ... + 13850168.

Almost surely, 2^55400666 is an apocalyptic number.

55400666 is a deficient number, since it is larger than the sum of its proper divisors (27700336).

55400666 is a wasteful number, since it uses less digits than its factorization.

55400666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27700335.

The product of its (nonzero) digits is 21600, while the sum is 32.

The square root of 55400666 is about 7443.1623655540. The cubic root of 55400666 is about 381.2164755615.

The spelling of 55400666 in words is "fifty-five million, four hundred thousand, six hundred sixty-six".