1977642 has 32 divisors (see below), whose sum is σ = 4484160. Its totient is φ = 645840.

The previous prime is 1977637. The next prime is 1977667. The reversal of 1977642 is 2467791.

It is a happy number.

1977642 is a `hidden beast` number, since 1 + 9 + 7 + 7 + 642 = 666.

It is a super-2 number, since 2×1977642² = 7822135760328, which contains 22 as substring.

It is a d-powerful number, because it can be written as 1 + 9⁶ + 7 + 7⁶ + 6⁷ + 4¹⁰ + 2⁵ .

It is a junction number, because it is equal to n+sod(n) for n = 1977597 and 1977606.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2517 + ... + 3207.

It is an arithmetic number, because the mean of its divisors is an integer number (140130).

2^1977642 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1977642, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2242080).

1977642 is an abundant number, since it is smaller than the sum of its proper divisors (2506518).

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

1977642 is a wasteful number, since it uses less digits than its factorization.

1977642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 755 (or 749 counting only the distinct ones).

The product of its digits is 21168, while the sum is 36.

The square root of 1977642 is about 1406.2865995237. The cubic root of 1977642 is about 125.5208559912.

The spelling of 1977642 in words is "one million, nine hundred seventy-seven thousand, six hundred forty-two".