669264381 has 12 divisors (see below), whose sum is σ = 1023581052. Its totient is φ = 419930496.

The previous prime is 669264377. The next prime is 669264391. The reversal of 669264381 is 183462966.

669264381 is a `hidden beast` number, since 6 + 6 + 9 + 264 + 381 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 347636025 + 321628356 = 18645^2 + 17934^2 .

It is not a de Polignac number, because 669264381 - 2² = 669264377 is a prime.

It is a super-2 number, since 2×669264381² = 895829623350626322, which contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669264311) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2186986 + ... + 2187291.

It is an arithmetic number, because the mean of its divisors is an integer number (85298421).

Almost surely, 2^669264381 is an apocalyptic number.

It is an amenable number.

669264381 is a deficient number, since it is larger than the sum of its proper divisors (354316671).

669264381 is a wasteful number, since it uses less digits than its factorization.

669264381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4374300 (or 4374297 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The square root of 669264381 is about 25870.1445879222. The cubic root of 669264381 is about 874.7136504093.

The spelling of 669264381 in words is "six hundred sixty-nine million, two hundred sixty-four thousand, three hundred eighty-one".