1976821940 has 96 divisors (see below), whose sum is σ = 4683813120. Its totient is φ = 697061376.

The previous prime is 1976821907. The next prime is 1976821943. The reversal of 1976821940 is 491286791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1976821943) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 320324 + ... + 326436.

It is an arithmetic number, because the mean of its divisors is an integer number (48789720).

Almost surely, 2^1976821940 is an apocalyptic number.

1976821940 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 1976821940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2341906560).

1976821940 is an abundant number, since it is smaller than the sum of its proper divisors (2706991180).

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

1976821940 is a wasteful number, since it uses less digits than its factorization.

1976821940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6201 (or 6199 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 47.

The square root of 1976821940 is about 44461.4657878033. The cubic root of 1976821940 is about 1255.0350386772.

The spelling of 1976821940 in words is "one billion, nine hundred seventy-six million, eight hundred twenty-one thousand, nine hundred forty".