99780438 has 16 divisors (see below), whose sum is σ = 210064320. Its totient is φ = 31509576.

The previous prime is 99780437. The next prime is 99780449. The reversal of 99780438 is 83408799.

It is a super-2 number, since 2×99780438² = 19912271614943688, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99780431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 437520 + ... + 437747.

It is an arithmetic number, because the mean of its divisors is an integer number (13129020).

Almost surely, 2^99780438 is an apocalyptic number.

99780438 is an abundant number, since it is smaller than the sum of its proper divisors (110283882).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

99780438 is a wasteful number, since it uses less digits than its factorization.

99780438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 875291.

The product of its (nonzero) digits is 435456, while the sum is 48.

The square root of 99780438 is about 9989.0158674416. The cubic root of 99780438 is about 463.8189289270.

The spelling of 99780438 in words is "ninety-nine million, seven hundred eighty thousand, four hundred thirty-eight".