1666486251 has 32 divisors (see below), whose sum is σ = 2698444800. Its totient is φ = 1011899520.

The previous prime is 1666486169. The next prime is 1666486271. The reversal of 1666486251 is 1526846661.

It is not a de Polignac number, because 1666486251 - 2¹¹ = 1666484203 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1666486197 and 1666486206.

It is not an unprimeable number, because it can be changed into a prime (1666486271) 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, 44331 + ... + 72788.

It is an arithmetic number, because the mean of its divisors is an integer number (84326400).

Almost surely, 2^1666486251 is an apocalyptic number.

1666486251 is a deficient number, since it is larger than the sum of its proper divisors (1031958549).

1666486251 is a wasteful number, since it uses less digits than its factorization.

1666486251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117176 (or 117170 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 1666486251 is about 40822.6193549606. The cubic root of 1666486251 is about 1185.5883186678.

The spelling of 1666486251 in words is "one billion, six hundred sixty-six million, four hundred eighty-six thousand, two hundred fifty-one".