1978923192 has 64 divisors (see below), whose sum is σ = 5116339200. Its totient is φ = 637182720.

The previous prime is 1978923181. The next prime is 1978923209. The reversal of 1978923192 is 2913298791.

It is a super-2 number, since 2×1978923192² = 7832273999670937728, which contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 458388 + ... + 462684.

It is an arithmetic number, because the mean of its divisors is an integer number (79942800).

Almost surely, 2^1978923192 is an apocalyptic number.

1978923192 is a gapful number since it is divisible by the number (12) 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 1978923192, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2558169600).

1978923192 is an abundant number, since it is smaller than the sum of its proper divisors (3137416008).

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

1978923192 is a wasteful number, since it uses less digits than its factorization.

1978923192 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4956 (or 4952 counting only the distinct ones).

The product of its digits is 489888, while the sum is 51.

The square root of 1978923192 is about 44485.0895469482. The cubic root of 1978923192 is about 1255.4795587431.

The spelling of 1978923192 in words is "one billion, nine hundred seventy-eight million, nine hundred twenty-three thousand, one hundred ninety-two".