102878640 has 80 divisors (see below), whose sum is σ = 354367200. Its totient is φ = 27433728.

The previous prime is 102878621. The next prime is 102878641. The reversal of 102878640 is 46878201.

102878640 is a `hidden beast` number, since 1 + 0 + 2 + 8 + 7 + 8 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (80).

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

It is a junction number, because it is equal to n+sod(n) for n = 102878595 and 102878604.

It is not an unprimeable number, because it can be changed into a prime (102878641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21655 + ... + 25974.

It is an arithmetic number, because the mean of its divisors is an integer number (4429590).

Almost surely, 2^102878640 is an apocalyptic number.

102878640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

102878640 is an abundant number, since it is smaller than the sum of its proper divisors (251488560).

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

102878640 is a wasteful number, since it uses less digits than its factorization.

102878640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47651 (or 47639 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 102878640 is about 10142.9108248076. The cubic root of 102878640 is about 468.5706385783.

The spelling of 102878640 in words is "one hundred two million, eight hundred seventy-eight thousand, six hundred forty".