1961154261 has 80 divisors (see below), whose sum is σ = 3355862400. Its totient is φ = 1130371200.

The previous prime is 1961154199. The next prime is 1961154311. The reversal of 1961154261 is 1624511691.

1961154261 is a `hidden beast` number, since 19 + 611 + 5 + 4 + 26 + 1 = 666.

It is not a de Polignac number, because 1961154261 - 2¹⁰ = 1961153237 is a prime.

It is a super-2 number, since 2×1961154261² = 7692252070876912242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1961154161) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1834035 + ... + 1835103.

It is an arithmetic number, because the mean of its divisors is an integer number (41948280).

Almost surely, 2^1961154261 is an apocalyptic number.

1961154261 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1961154261 is a deficient number, since it is larger than the sum of its proper divisors (1394708139).

1961154261 is a wasteful number, since it uses less digits than its factorization.

1961154261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1192 (or 1183 counting only the distinct ones).

The product of its digits is 12960, while the sum is 36.

The square root of 1961154261 is about 44284.9213728556. The cubic root of 1961154261 is about 1251.7105671137.

The spelling of 1961154261 in words is "one billion, nine hundred sixty-one million, one hundred fifty-four thousand, two hundred sixty-one".