1979540 has 24 divisors (see below), whose sum is σ = 4301640. Its totient is φ = 764288.

The previous prime is 1979539. The next prime is 1979543. The reversal of 1979540 is 459791.

It can be written as a sum of positive squares in 4 ways, for example, as 643204 + 1336336 = 802^2 + 1156^2 .

It is a super-2 number, since 2×1979540² = 7837157223200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1979540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1979543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1127 + ... + 2286.

It is an arithmetic number, because the mean of its divisors is an integer number (179235).

2^1979540 is an apocalyptic number.

1979540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1979540 is an abundant number, since it is smaller than the sum of its proper divisors (2322100).

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

1979540 is a wasteful number, since it uses less digits than its factorization.

1979540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3451 (or 3449 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 35.

The square root of 1979540 is about 1406.9612645699. The cubic root of 1979540 is about 125.5609984791.

The spelling of 1979540 in words is "one million, nine hundred seventy-nine thousand, five hundred forty".