669406654440 has 96 divisors (see below), whose sum is σ = 2175777045000. Its totient is φ = 178491586560.

The previous prime is 669406654393. The next prime is 669406654487. The reversal of 669406654440 is 44456604966.

669406654440 is a `hidden beast` number, since 6 + 6 + 94 + 0 + 6 + 6 + 544 + 4 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (669406654393) and next prime (669406654487).

It can be written as a sum of positive squares in 4 ways, for example, as 145193005764 + 524213648676 = 381042^2 + 724026^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3993436 + ... + 4157684.

Almost surely, 2^669406654440 is an apocalyptic number.

669406654440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

669406654440 is an abundant number, since it is smaller than the sum of its proper divisors (1506370390560).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

669406654440 is a wasteful number, since it uses less digits than its factorization.

669406654440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175587 (or 175580 counting only the distinct ones).

The product of its (nonzero) digits is 14929920, while the sum is 54.

The spelling of 669406654440 in words is "six hundred sixty-nine billion, four hundred six million, six hundred fifty-four thousand, four hundred forty".