7491991947 has 16 divisors (see below), whose sum is σ = 10904813568. Its totient is φ = 4537530080.

The previous prime is 7491991937. The next prime is 7491991961.

7491991947 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 7491991947 - 2⁶ = 7491991883 is a prime.

It is a super-2 number, since 2×7491991947² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (7491991937) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26763 + ... + 125300.

It is an arithmetic number, because the mean of its divisors is an integer number (681550848).

Almost surely, 2^7491991947 is an apocalyptic number.

7491991947 is a deficient number, since it is larger than the sum of its proper divisors (3412821621).

7491991947 is a wasteful number, since it uses less digits than its factorization.

7491991947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153570.

The product of its digits is 5143824, while the sum is 60.

The square root of 7491991947 is about 86556.2935146833. The cubic root of 7491991947 is about 1956.7368954236.

The spelling of 7491991947 in words is "seven billion, four hundred ninety-one million, nine hundred ninety-one thousand, nine hundred forty-seven".