1949447681 has 4 divisors (see below), whose sum is σ = 2064121092. Its totient is φ = 1834774272.

The previous prime is 1949447677. The next prime is 1949447693. The reversal of 1949447681 is 1867449491.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 844483600 + 1104964081 = 29060^2 + 33241^2 .

It is a cyclic number.

It is not a de Polignac number, because 1949447681 - 2² = 1949447677 is a prime.

It is a super-2 number, since 2×1949447681² = 7600692521912555522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1949447081) 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, 57336680 + ... + 57336713.

It is an arithmetic number, because the mean of its divisors is an integer number (516030273).

Almost surely, 2^1949447681 is an apocalyptic number.

It is an amenable number.

1949447681 is a deficient number, since it is larger than the sum of its proper divisors (114673411).

1949447681 is a wasteful number, since it uses less digits than its factorization.

1949447681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114673410.

The product of its digits is 1741824, while the sum is 53.

The square root of 1949447681 is about 44152.5501075532. The cubic root of 1949447681 is about 1249.2150124188.

It can be divided in two parts, 19 and 49447681, that multiplied together give a palindrome (939505939).

The spelling of 1949447681 in words is "one billion, nine hundred forty-nine million, four hundred forty-seven thousand, six hundred eighty-one".