400002680 has 96 divisors (see below), whose sum is σ = 1142184240. Its totient is φ = 124669440.

The previous prime is 400002679. The next prime is 400002689. The reversal of 400002680 is 86200004.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400002689) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12284 + ... + 30836.

Almost surely, 2^400002680 is an apocalyptic number.

400002680 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400002680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (571092120).

400002680 is an abundant number, since it is smaller than the sum of its proper divisors (742181560).

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

400002680 is a wasteful number, since it uses less digits than its factorization.

400002680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18589 (or 18578 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 400002680 is about 20000.0669998878. The cubic root of 400002680 is about 736.8079452585.

Adding to 400002680 its reverse (86200004), we get a palindrome (486202684).

The spelling of 400002680 in words is "four hundred million, two thousand, six hundred eighty".