1978179840 has 1152 divisors, whose sum is σ = 9395205120. Its totient is φ = 382205952.

The previous prime is 1978179793. The next prime is 1978179887. The reversal of 1978179840 is 489718791.

It is an interprime number because it is at equal distance from previous prime (1978179793) and next prime (1978179887).

It is a tau number, because it is divible by the number of its divisors (1152).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 53464302 + ... + 53464338.

It is an arithmetic number, because the mean of its divisors is an integer number (8155560).

Almost surely, 2^1978179840 is an apocalyptic number.

1978179840 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 1978179840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4697602560).

1978179840 is an abundant number, since it is smaller than the sum of its proper divisors (7417025280).

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

1978179840 is a wasteful number, since it uses less digits than its factorization.

1978179840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104 (or 84 counting only the distinct ones).

The product of its (nonzero) digits is 1016064, while the sum is 54.

The square root of 1978179840 is about 44476.7336930220. The cubic root of 1978179840 is about 1255.3223385396.

The spelling of 1978179840 in words is "one billion, nine hundred seventy-eight million, one hundred seventy-nine thousand, eight hundred forty".