99779121 has 60 divisors (see below), whose sum is σ = 166603932. Its totient is φ = 59439744.

The previous prime is 99779081. The next prime is 99779131. The reversal of 99779121 is 12197799.

It can be written as a sum of positive squares in 6 ways, for example, as 2480625 + 97298496 = 1575^2 + 9864^2 .

It is not a de Polignac number, because 99779121 - 2¹⁴ = 99762737 is a prime.

It is a super-3 number, since 3×99779121³ (a number of 25 digits) contains 333 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99779131) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 506395 + ... + 506591.

Almost surely, 2^99779121 is an apocalyptic number.

It is an amenable number.

99779121 is a deficient number, since it is larger than the sum of its proper divisors (66824811).

99779121 is a wasteful number, since it uses less digits than its factorization.

99779121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272 (or 250 counting only the distinct ones).

The product of its digits is 71442, while the sum is 45.

The square root of 99779121 is about 9988.9499448140. The cubic root of 99779121 is about 463.8168882724.

The spelling of 99779121 in words is "ninety-nine million, seven hundred seventy-nine thousand, one hundred twenty-one".