66251223 has 16 divisors (see below), whose sum is σ = 99497440. Its totient is φ = 43561152.

The previous prime is 66251221. The next prime is 66251231. The reversal of 66251223 is 32215266.

66251223 is a `hidden beast` number, since 6 + 625 + 12 + 23 = 666.

It is not a de Polignac number, because 66251223 - 2¹ = 66251221 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66251221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14836 + ... + 18777.

It is an arithmetic number, because the mean of its divisors is an integer number (6218590).

Almost surely, 2^66251223 is an apocalyptic number.

66251223 is a deficient number, since it is larger than the sum of its proper divisors (33246217).

66251223 is a wasteful number, since it uses less digits than its factorization.

66251223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33695 (or 33689 counting only the distinct ones).

The product of its digits is 4320, while the sum is 27.

The square root of 66251223 is about 8139.4854259959. The cubic root of 66251223 is about 404.6361066094.

Adding to 66251223 its reverse (32215266), we get a palindrome (98466489).

The spelling of 66251223 in words is "sixty-six million, two hundred fifty-one thousand, two hundred twenty-three".