99997906 has 4 divisors (see below), whose sum is σ = 149996862. Its totient is φ = 49998952.

The previous prime is 99997901. The next prime is 99997907. The reversal of 99997906 is 60979999.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60979999 = 2089 ⋅29191.

It can be written as a sum of positive squares in only one way, i.e., 92948881 + 7049025 = 9641^2 + 2655^2 .

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (99997901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 24999475 + ... + 24999478.

Almost surely, 2^99997906 is an apocalyptic number.

99997906 is a deficient number, since it is larger than the sum of its proper divisors (49998956).

99997906 is a wasteful number, since it uses less digits than its factorization.

99997906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49998955.

The product of its (nonzero) digits is 2480058, while the sum is 58.

The square root of 99997906 is about 9999.8952994519. The cubic root of 99997906 is about 464.1556435097.

The spelling of 99997906 in words is "ninety-nine million, nine hundred ninety-seven thousand, nine hundred six".