66620410 has 8 divisors (see below), whose sum is σ = 119916756. Its totient is φ = 26648160.

The previous prime is 66620401. The next prime is 66620413. The reversal of 66620410 is 1402666.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 66145689 + 474721 = 8133^2 + 689^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (66620413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3331011 + ... + 3331030.

Almost surely, 2^66620410 is an apocalyptic number.

66620410 is a deficient number, since it is larger than the sum of its proper divisors (53296346).

66620410 is a wasteful number, since it uses less digits than its factorization.

66620410 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6662048.

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

The square root of 66620410 is about 8162.1326869881. The cubic root of 66620410 is about 405.3863305432.

The spelling of 66620410 in words is "sixty-six million, six hundred twenty thousand, four hundred ten".