19239961 has 4 divisors (see below), whose sum is σ = 20719972. Its totient is φ = 17759952.

The previous prime is 19239929. The next prime is 19240019. The reversal of 19239961 is 16993291.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16993291 = 7 ⋅2427613.

It can be written as a sum of positive squares in 2 ways, for example, as 1440000 + 17799961 = 1200^2 + 4219^2 .

It is a cyclic number.

It is not a de Polignac number, because 19239961 - 2⁵ = 19239929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19239161) 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, 739986 + ... + 740011.

It is an arithmetic number, because the mean of its divisors is an integer number (5179993).

Almost surely, 2^19239961 is an apocalyptic number.

It is an amenable number.

19239961 is a deficient number, since it is larger than the sum of its proper divisors (1480011).

19239961 is a wasteful number, since it uses less digits than its factorization.

19239961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1480010.

The product of its digits is 26244, while the sum is 40.

The square root of 19239961 is about 4386.3379942727. The cubic root of 19239961 is about 267.9588235914.

The spelling of 19239961 in words is "nineteen million, two hundred thirty-nine thousand, nine hundred sixty-one".