1972861 has 4 divisors (see below), whose sum is σ = 2152224. Its totient is φ = 1793500.

The previous prime is 1972849. The next prime is 1972889. The reversal of 1972861 is 1682791.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1682791 = 11 ⋅152981.

It is a cyclic number.

It is not a de Polignac number, because 1972861 - 2⁵ = 1972829 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1972891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 89665 + ... + 89686.

It is an arithmetic number, because the mean of its divisors is an integer number (538056).

2^1972861 is an apocalyptic number.

1972861 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1972861 is a deficient number, since it is larger than the sum of its proper divisors (179363).

1972861 is a wasteful number, since it uses less digits than its factorization.

1972861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179362.

The product of its digits is 6048, while the sum is 34.

The square root of 1972861 is about 1404.5857040423. The cubic root of 1972861 is about 125.4196244132.

The spelling of 1972861 in words is "one million, nine hundred seventy-two thousand, eight hundred sixty-one".