102665640 has 256 divisors, whose sum is σ = 394813440. Its totient is φ = 20736000.

The previous prime is 102665621. The next prime is 102665653. The reversal of 102665640 is 46566201.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 102665598 and 102665607.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 378705 + ... + 378975.

It is an arithmetic number, because the mean of its divisors is an integer number (1542240).

Almost surely, 2^102665640 is an apocalyptic number.

102665640 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 102665640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (197406720).

102665640 is an abundant number, since it is smaller than the sum of its proper divisors (292147800).

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

102665640 is a wasteful number, since it uses less digits than its factorization.

102665640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344 (or 340 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 102665640 is about 10132.4054399733. The cubic root of 102665640 is about 468.2470388349.

It can be divided in two parts, 1026 and 65640, that added together give a palindrome (66666).

The spelling of 102665640 in words is "one hundred two million, six hundred sixty-five thousand, six hundred forty".