1978388 has 24 divisors (see below), whose sum is σ = 3598560. Its totient is φ = 951200.

The previous prime is 1978363. The next prime is 1978393. The reversal of 1978388 is 8838791.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19538 + ... + 19638.

It is an arithmetic number, because the mean of its divisors is an integer number (149940).

2^1978388 is an apocalyptic number.

It is an amenable number.

1978388 is a deficient number, since it is larger than the sum of its proper divisors (1620172).

1978388 is a wasteful number, since it uses less digits than its factorization.

1978388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247 (or 245 counting only the distinct ones).

The product of its digits is 96768, while the sum is 44.

The square root of 1978388 is about 1406.5518120567. The cubic root of 1978388 is about 125.5366368701.

The spelling of 1978388 in words is "one million, nine hundred seventy-eight thousand, three hundred eighty-eight".