1665565854 has 64 divisors (see below), whose sum is σ = 3615155712. Its totient is φ = 509644800.

The previous prime is 1665565843. The next prime is 1665565877. The reversal of 1665565854 is 4585655661.

It is a super-2 number, since 2×1665565854² = 5548219228021498632, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1665565797 and 1665565806.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 701289 + ... + 703659.

It is an arithmetic number, because the mean of its divisors is an integer number (56486808).

Almost surely, 2^1665565854 is an apocalyptic number.

1665565854 is an abundant number, since it is smaller than the sum of its proper divisors (1949589858).

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

1665565854 is a wasteful number, since it uses less digits than its factorization.

1665565854 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2561.

The product of its digits is 4320000, while the sum is 51.

The square root of 1665565854 is about 40811.3446727745. The cubic root of 1665565854 is about 1185.3700124593.

The spelling of 1665565854 in words is "one billion, six hundred sixty-five million, five hundred sixty-five thousand, eight hundred fifty-four".