99790381 has 4 divisors (see below), whose sum is σ = 99853564. Its totient is φ = 99727200.

The previous prime is 99790373. The next prime is 99790409. The reversal of 99790381 is 18309799.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18309799 = 17 ⋅1077047.

It can be written as a sum of positive squares in 2 ways, for example, as 82192356 + 17598025 = 9066^2 + 4195^2 .

It is a cyclic number.

It is not a de Polignac number, because 99790381 - 2³ = 99790373 is a prime.

It is a super-2 number, since 2×99790381² = 19916240280250322, which contains 22 as substring.

It is a deceptive number, since it divides R_99790380.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99790331) 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, 29160 + ... + 32401.

It is an arithmetic number, because the mean of its divisors is an integer number (24963391).

Almost surely, 2^99790381 is an apocalyptic number.

It is an amenable number.

99790381 is a deficient number, since it is larger than the sum of its proper divisors (63183).

99790381 is a wasteful number, since it uses less digits than its factorization.

99790381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63182.

The product of its (nonzero) digits is 122472, while the sum is 46.

The square root of 99790381 is about 9989.5135517201. The cubic root of 99790381 is about 463.8343347471.

It can be divided in two parts, 997 and 90381, that added together give a triangular number (91378 = T₄₂₇).

The spelling of 99790381 in words is "ninety-nine million, seven hundred ninety thousand, three hundred eighty-one".