1961091 has 40 divisors (see below), whose sum is σ = 3345408. Its totient is φ = 1134000.

The previous prime is 1961083. The next prime is 1961093. The reversal of 1961091 is 1901691.

It is not a de Polignac number, because 1961091 - 2³ = 1961083 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1961093) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 27586 + ... + 27656.

2^1961091 is an apocalyptic number.

1961091 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1961091 is a deficient number, since it is larger than the sum of its proper divisors (1384317).

1961091 is a wasteful number, since it uses less digits than its factorization.

1961091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125 (or 116 counting only the distinct ones).

The product of its (nonzero) digits is 486, while the sum is 27.

The square root of 1961091 is about 1400.3895886502. The cubic root of 1961091 is about 125.1697108150.

It can be divided in two parts, 19610 and 91, that added together give a triangular number (19701 = T₁₉₈).

The spelling of 1961091 in words is "one million, nine hundred sixty-one thousand, ninety-one".