400650138 has 192 divisors, whose sum is σ = 1107025920. Its totient is φ = 106142400.

The previous prime is 400650127. The next prime is 400650139. The reversal of 400650138 is 831056004.

400650138 is a `hidden beast` number, since 4 + 0 + 0 + 650 + 1 + 3 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (400650139) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3058333 + ... + 3058463.

It is an arithmetic number, because the mean of its divisors is an integer number (5765760).

Almost surely, 2^400650138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400650138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (553512960).

400650138 is an abundant number, since it is smaller than the sum of its proper divisors (706375782).

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

400650138 is a wasteful number, since it uses less digits than its factorization.

400650138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215 (or 203 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 400650138 is about 20016.2468509958. The cubic root of 400650138 is about 737.2052717954.

The spelling of 400650138 in words is "four hundred million, six hundred fifty thousand, one hundred thirty-eight".