9997906042 has 4 divisors (see below), whose sum is σ = 14996859066. Its totient is φ = 4998953020.

The previous prime is 9997906033. The next prime is 9997906043. The reversal of 9997906042 is 2406097999.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2406097999 = 653 ⋅3684683.

It can be written as a sum of positive squares in only one way, i.e., 9856319841 + 141586201 = 99279^2 + 11899^2 .

It is not an unprimeable number, because it can be changed into a prime (9997906043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2499476509 + ... + 2499476512.

Almost surely, 2^9997906042 is an apocalyptic number.

9997906042 is a deficient number, since it is larger than the sum of its proper divisors (4998953024).

9997906042 is a wasteful number, since it uses less digits than its factorization.

9997906042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4998953023.

The product of its (nonzero) digits is 2204496, while the sum is 55.

The square root of 9997906042 is about 99989.5296618601. The cubic root of 9997906042 is about 2154.2843030094.

The spelling of 9997906042 in words is "nine billion, nine hundred ninety-seven million, nine hundred six thousand, forty-two".