2129950781 has 8 divisors (see below), whose sum is σ = 2443019520. Its totient is φ = 1819079568.

The previous prime is 2129950751. The next prime is 2129950853. The reversal of 2129950781 is 1870599212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2129950781 - 2⁶ = 2129950717 is a prime.

It is a super-2 number, since 2×2129950781² = 9073380658965019922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2129950751) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 547301 + ... + 551178.

It is an arithmetic number, because the mean of its divisors is an integer number (305377440).

Almost surely, 2^2129950781 is an apocalyptic number.

It is an amenable number.

2129950781 is a deficient number, since it is larger than the sum of its proper divisors (313068739).

2129950781 is a wasteful number, since it uses less digits than its factorization.

2129950781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1098763.

The product of its (nonzero) digits is 90720, while the sum is 44.

The square root of 2129950781 is about 46151.3898057252. The cubic root of 2129950781 is about 1286.6384407334.

The spelling of 2129950781 in words is "two billion, one hundred twenty-nine million, nine hundred fifty thousand, seven hundred eighty-one".