990756493 has 4 divisors (see below), whose sum is σ = 1024920540. Its totient is φ = 956592448.

The previous prime is 990756479. The next prime is 990756499. The reversal of 990756493 is 394657099.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 394657099 = 2003 ⋅197033.

It can be written as a sum of positive squares in 2 ways, for example, as 250209124 + 740547369 = 15818^2 + 27213^2 .

It is a cyclic number.

It is not a de Polignac number, because 990756493 - 2¹³ = 990748301 is a prime.

It is a super-3 number, since 3×990756493³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 990756493.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990756499) 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, 17081980 + ... + 17082037.

It is an arithmetic number, because the mean of its divisors is an integer number (256230135).

Almost surely, 2^990756493 is an apocalyptic number.

It is an amenable number.

990756493 is a deficient number, since it is larger than the sum of its proper divisors (34164047).

990756493 is a wasteful number, since it uses less digits than its factorization.

990756493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34164046.

The product of its (nonzero) digits is 1837080, while the sum is 52.

The square root of 990756493 is about 31476.2846123871. The cubic root of 990756493 is about 996.9092883428.

The spelling of 990756493 in words is "nine hundred ninety million, seven hundred fifty-six thousand, four hundred ninety-three".