1961555 has 16 divisors (see below), whose sum is σ = 2528064. Its totient is φ = 1457280.

The previous prime is 1961551. The next prime is 1961581. The reversal of 1961555 is 5551691.

It is not a de Polignac number, because 1961555 - 2² = 1961551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1961551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4025 + ... + 4485.

It is an arithmetic number, because the mean of its divisors is an integer number (158004).

2^1961555 is an apocalyptic number.

1961555 is a deficient number, since it is larger than the sum of its proper divisors (566509).

1961555 is a wasteful number, since it uses less digits than its factorization.

1961555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 526.

The product of its digits is 6750, while the sum is 32.

The square root of 1961555 is about 1400.5552470360. Note that the first 3 decimals coincide. The cubic root of 1961555 is about 125.1795818792.

The spelling of 1961555 in words is "one million, nine hundred sixty-one thousand, five hundred fifty-five".