28377780 has 24 divisors (see below), whose sum is σ = 79457952. Its totient is φ = 7567392.

The previous prime is 28377757. The next prime is 28377787. The reversal of 28377780 is 8777382.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28377787) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 236422 + ... + 236541.

It is an arithmetic number, because the mean of its divisors is an integer number (3310748).

Almost surely, 2^28377780 is an apocalyptic number.

28377780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28377780 is an abundant number, since it is smaller than the sum of its proper divisors (51080172).

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

28377780 is a wasteful number, since it uses less digits than its factorization.

28377780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472975 (or 472973 counting only the distinct ones).

The product of its (nonzero) digits is 131712, while the sum is 42.

The square root of 28377780 is about 5327.0798755040. The cubic root of 28377780 is about 305.0184706184.

The spelling of 28377780 in words is "twenty-eight million, three hundred seventy-seven thousand, seven hundred eighty".