402779520 has 512 divisors, whose sum is σ = 1686182400. Its totient is φ = 89579520.

The previous prime is 402779513. The next prime is 402779527. The reversal of 402779520 is 25977204.

402779520 is a `hidden beast` number, since 40 + 27 + 79 + 520 = 666.

It is an interprime number because it is at equal distance from previous prime (402779513) and next prime (402779527).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402779527) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2470959 + ... + 2471121.

It is an arithmetic number, because the mean of its divisors is an integer number (3293325).

Almost surely, 2^402779520 is an apocalyptic number.

402779520 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 402779520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (843091200).

402779520 is an abundant number, since it is smaller than the sum of its proper divisors (1283402880).

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

402779520 is a wasteful number, since it uses less digits than its factorization.

402779520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215 (or 197 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The square root of 402779520 is about 20069.3677030444. The cubic root of 402779520 is about 738.5090017570.

The spelling of 402779520 in words is "four hundred two million, seven hundred seventy-nine thousand, five hundred twenty".