386561840 has 160 divisors (see below), whose sum is σ = 1105643520. Its totient is φ = 122729472.

The previous prime is 386561809. The next prime is 386561863. The reversal of 386561840 is 48165683.

It is a super-2 number, since 2×386561840² = 298860112288371200, which contains 22 as substring.

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, 499694 + ... + 500466.

It is an arithmetic number, because the mean of its divisors is an integer number (6910272).

Almost surely, 2^386561840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 386561840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (552821760).

386561840 is an abundant number, since it is smaller than the sum of its proper divisors (719081680).

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

386561840 is a wasteful number, since it uses less digits than its factorization.

386561840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 859 (or 853 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 41.

The square root of 386561840 is about 19661.1759566919. The cubic root of 386561840 is about 728.4610351039.

It can be divided in two parts, 3865 and 61840, that multiplied together give a square (239011600 = 15460²).

The spelling of 386561840 in words is "three hundred eighty-six million, five hundred sixty-one thousand, eight hundred forty".