1961155 has 16 divisors (see below), whose sum is σ = 2715840. Its totient is φ = 1331712.

The previous prime is 1961147. The next prime is 1961173. The reversal of 1961155 is 5511691.

It is a 9-Lehmer number, since φ(1961155) divides (1961155-1)⁹.

It is a cyclic number.

It is not a de Polignac number, because 1961155 - 2³ = 1961147 is a prime.

It is a super-2 number, since 2×1961155² = 7692257868050, which contains 22 as substring.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 4591 + ... + 4999.

It is an arithmetic number, because the mean of its divisors is an integer number (169740).

2^1961155 is an apocalyptic number.

1961155 is a deficient number, since it is larger than the sum of its proper divisors (754685).

1961155 is a wasteful number, since it uses less digits than its factorization.

1961155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 558.

The product of its digits is 1350, while the sum is 28.

The square root of 1961155 is about 1400.4124392478. The cubic root of 1961155 is about 125.1710724336.

It can be divided in two parts, 1961 and 155, that added together give a square (2116 = 46²).

The spelling of 1961155 in words is "one million, nine hundred sixty-one thousand, one hundred fifty-five".