1961889929 has 4 divisors (see below), whose sum is σ = 1976866320. Its totient is φ = 1946913540.

The previous prime is 1961889911. The next prime is 1961889931. The reversal of 1961889929 is 9299881691.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9299881691 = 1571 ⋅5919721.

It is a cyclic number.

It is not a de Polignac number, because 1961889929 - 2²⁴ = 1945112713 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1961889989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7487999 + ... + 7488260.

It is an arithmetic number, because the mean of its divisors is an integer number (494216580).

Almost surely, 2^1961889929 is an apocalyptic number.

It is an amenable number.

1961889929 is a deficient number, since it is larger than the sum of its proper divisors (14976391).

1961889929 is a wasteful number, since it uses less digits than its factorization.

1961889929 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14976390.

The product of its digits is 5038848, while the sum is 62.

The square root of 1961889929 is about 44293.2266718062. The cubic root of 1961889929 is about 1251.8670613969.

The spelling of 1961889929 in words is "one billion, nine hundred sixty-one million, eight hundred eighty-nine thousand, nine hundred twenty-nine".