1961945 has 4 divisors (see below), whose sum is σ = 2354340. Its totient is φ = 1569552.

The previous prime is 1961933. The next prime is 1961957. The reversal of 1961945 is 5491691.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5491691 = 541 ⋅10151.

It is an interprime number because it is at equal distance from previous prime (1961933) and next prime (1961957).

It can be written as a sum of positive squares in 2 ways, for example, as 1459264 + 502681 = 1208^2 + 709^2 .

It is a cyclic number.

It is not a de Polignac number, because 1961945 - 2⁴ = 1961929 is a prime.

It is a d-powerful number, because it can be written as 1 + 9 + 6⁵ + 1 + 9 + 4⁵ + 5⁹ .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 196190 + ... + 196199.

It is an arithmetic number, because the mean of its divisors is an integer number (588585).

2^1961945 is an apocalyptic number.

It is an amenable number.

1961945 is a deficient number, since it is larger than the sum of its proper divisors (392395).

1961945 is an equidigital number, since it uses as much as digits as its factorization.

1961945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392394.

The product of its digits is 9720, while the sum is 35.

The square root of 1961945 is about 1400.6944706109. The cubic root of 1961945 is about 125.1878774750.

The spelling of 1961945 in words is "one million, nine hundred sixty-one thousand, nine hundred forty-five".