1978550 has 24 divisors (see below), whose sum is σ = 4206576. Its totient is φ = 678240.

The previous prime is 1978541. The next prime is 1978567. The reversal of 1978550 is 558791.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 1978550.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 2477 + ... + 3176.

It is an arithmetic number, because the mean of its divisors is an integer number (175274).

2^1978550 is an apocalyptic number.

1978550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1978550 is an abundant number, since it is smaller than the sum of its proper divisors (2228026).

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

1978550 is a wasteful number, since it uses less digits than its factorization.

1978550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5672 (or 5667 counting only the distinct ones).

The product of its (nonzero) digits is 12600, while the sum is 35.

The square root of 1978550 is about 1406.6093985183. The cubic root of 1978550 is about 125.5400632927.

The spelling of 1978550 in words is "one million, nine hundred seventy-eight thousand, five hundred fifty".