102205440 has 144 divisors (see below), whose sum is σ = 354545100. Its totient is φ = 27230208.

The previous prime is 102205429. The next prime is 102205457. The reversal of 102205440 is 44502201.

102205440 is a `hidden beast` number, since 1 + 0 + 220 + 5 + 440 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 86713344 + 15492096 = 9312^2 + 3936^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 91606 + ... + 92714.

Almost surely, 2^102205440 is an apocalyptic number.

102205440 is a gapful number since it is divisible by the number (10) 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 102205440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (177272550).

102205440 is an abundant number, since it is smaller than the sum of its proper divisors (252339660).

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

102205440 is a wasteful number, since it uses less digits than its factorization.

102205440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1142 (or 1119 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 102205440 is about 10109.6706177798. The cubic root of 102205440 is about 467.5463497946.

Adding to 102205440 its reverse (44502201), we get a palindrome (146707641).

The spelling of 102205440 in words is "one hundred two million, two hundred five thousand, four hundred forty".