101662991 has 4 divisors (see below), whose sum is σ = 101745000. Its totient is φ = 101580984.

The previous prime is 101662973. The next prime is 101662999. The reversal of 101662991 is 199266101.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 101662991 - 2²⁶ = 34554127 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101662999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39116 + ... + 41633.

It is an arithmetic number, because the mean of its divisors is an integer number (25436250).

Almost surely, 2^101662991 is an apocalyptic number.

101662991 is a deficient number, since it is larger than the sum of its proper divisors (82009).

101662991 is an equidigital number, since it uses as much as digits as its factorization.

101662991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82008.

The product of its (nonzero) digits is 5832, while the sum is 35.

The square root of 101662991 is about 10082.8067025010. The cubic root of 101662991 is about 466.7177244023.

The spelling of 101662991 in words is "one hundred one million, six hundred sixty-two thousand, nine hundred ninety-one".