402787840 has 360 divisors, whose sum is σ = 1280509560. Its totient is φ = 120766464.

The previous prime is 402787831. The next prime is 402787841. The reversal of 402787840 is 48787204.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 402787793 and 402787802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402787841) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 21199351 + ... + 21199369.

It is an arithmetic number, because the mean of its divisors is an integer number (3556971).

Almost surely, 2^402787840 is an apocalyptic number.

402787840 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 402787840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (640254780).

402787840 is an abundant number, since it is smaller than the sum of its proper divisors (877721720).

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

402787840 is a wasteful number, since it uses less digits than its factorization.

402787840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 100352, while the sum is 40.

The square root of 402787840 is about 20069.5749830434. The cubic root of 402787840 is about 738.5140867165.

It can be divided in two parts, 40 and 2787840, that multiplied together give a square (111513600 = 10560²).

The spelling of 402787840 in words is "four hundred two million, seven hundred eighty-seven thousand, eight hundred forty".