66624261 has 32 divisors (see below), whose sum is σ = 102850560. Its totient is φ = 37963200.

The previous prime is 66624227. The next prime is 66624269. The reversal of 66624261 is 16242666.

It is not a de Polignac number, because 66624261 - 2⁷ = 66624133 is a prime.

It is a super-2 number, since 2×66624261² = 8877584307592242, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66624269) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 45580 + ... + 47018.

It is an arithmetic number, because the mean of its divisors is an integer number (3214080).

Almost surely, 2^66624261 is an apocalyptic number.

66624261 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

66624261 is a deficient number, since it is larger than the sum of its proper divisors (36226299).

66624261 is a wasteful number, since it uses less digits than its factorization.

66624261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1537.

The product of its digits is 20736, while the sum is 33.

The square root of 66624261 is about 8162.3685900601. The cubic root of 66624261 is about 405.3941415262.

The spelling of 66624261 in words is "sixty-six million, six hundred twenty-four thousand, two hundred sixty-one".