615402240 has 144 divisors (see below), whose sum is σ = 2011688448. Its totient is φ = 160247808.

The previous prime is 615402157. The next prime is 615402299. The reversal of 615402240 is 42204516.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 615402240.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 163257 + ... + 166983.

Almost surely, 2^615402240 is an apocalyptic number.

615402240 is a gapful number since it is divisible by the number (60) 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 615402240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1005844224).

615402240 is an abundant number, since it is smaller than the sum of its proper divisors (1396286208).

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

615402240 is a wasteful number, since it uses less digits than its factorization.

615402240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3794 (or 3780 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 615402240 is about 24807.3021507781. The cubic root of 615402240 is about 850.5888606993.

Adding to 615402240 its reverse (42204516), we get a palindrome (657606756).

The spelling of 615402240 in words is "six hundred fifteen million, four hundred two thousand, two hundred forty".