69920991 has 18 divisors (see below), whose sum is σ = 117487032. Its totient is φ = 39954600.

The previous prime is 69920971. The next prime is 69921023. The reversal of 69920991 is 19902996.

It is a happy number.

It is not a de Polignac number, because 69920991 - 2⁶ = 69920927 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (69920911) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 78835 + ... + 79716.

Almost surely, 2^69920991 is an apocalyptic number.

69920991 is a deficient number, since it is larger than the sum of its proper divisors (47566041).

69920991 is a wasteful number, since it uses less digits than its factorization.

69920991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158571 (or 158561 counting only the distinct ones).

The product of its (nonzero) digits is 78732, while the sum is 45.

The square root of 69920991 is about 8361.8772413855. The cubic root of 69920991 is about 411.9734151162.

The spelling of 69920991 in words is "sixty-nine million, nine hundred twenty thousand, nine hundred ninety-one".