991257742 has 8 divisors (see below), whose sum is σ = 1487245536. Its totient is φ = 495509232.

The previous prime is 991257739. The next prime is 991257791. The reversal of 991257742 is 247752199.

It is a happy number.

991257742 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×991257742² = 1965183822149877128, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 991257692 and 991257701.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49078 + ... + 66265.

It is an arithmetic number, because the mean of its divisors is an integer number (185905692).

Almost surely, 2^991257742 is an apocalyptic number.

991257742 is a deficient number, since it is larger than the sum of its proper divisors (495987794).

991257742 is a wasteful number, since it uses less digits than its factorization.

991257742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119642.

The product of its digits is 317520, while the sum is 46.

The square root of 991257742 is about 31484.2459334824. The cubic root of 991257742 is about 997.0773806173.

The spelling of 991257742 in words is "nine hundred ninety-one million, two hundred fifty-seven thousand, seven hundred forty-two".