49999661 has 4 divisors (see below), whose sum is σ = 50019324. Its totient is φ = 49980000.

The previous prime is 49999643. The next prime is 49999667. The reversal of 49999661 is 16699994.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16699994 = 2 ⋅8349997.

It can be written as a sum of positive squares in 2 ways, for example, as 25694761 + 24304900 = 5069^2 + 4930^2 .

It is a cyclic number.

It is not a de Polignac number, because 49999661 - 2⁶ = 49999597 is a prime.

It is a super-3 number, since 3×49999661³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

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 (49999667) 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, 5330 + ... + 11331.

It is an arithmetic number, because the mean of its divisors is an integer number (12504831).

Almost surely, 2^49999661 is an apocalyptic number.

It is an amenable number.

49999661 is a deficient number, since it is larger than the sum of its proper divisors (19663).

49999661 is a wasteful number, since it uses less digits than its factorization.

49999661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19662.

The product of its digits is 944784, while the sum is 53.

The square root of 49999661 is about 7071.0438409050. The cubic root of 49999661 is about 368.4023172710.

The spelling of 49999661 in words is "forty-nine million, nine hundred ninety-nine thousand, six hundred sixty-one".