385778731 has 16 divisors (see below), whose sum is σ = 420336000. Its totient is φ = 351946368.

The previous prime is 385778693. The next prime is 385778741. The reversal of 385778731 is 137877583.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-385778731 is a prime.

It is a super-2 number, since 2×385778731² = 297650458583940722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (385778741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 536190 + ... + 536908.

It is an arithmetic number, because the mean of its divisors is an integer number (26271000).

Almost surely, 2^385778731 is an apocalyptic number.

385778731 is a deficient number, since it is larger than the sum of its proper divisors (34557269).

385778731 is a wasteful number, since it uses less digits than its factorization.

385778731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1158.

The product of its digits is 987840, while the sum is 49.

The square root of 385778731 is about 19641.2507493795. The cubic root of 385778731 is about 727.9687895437.

The spelling of 385778731 in words is "three hundred eighty-five million, seven hundred seventy-eight thousand, seven hundred thirty-one".