101661531 has 4 divisors (see below), whose sum is σ = 135548712. Its totient is φ = 67774352.

The previous prime is 101661487. The next prime is 101661613. The reversal of 101661531 is 135166101.

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 101661531 - 2⁹ = 101661019 is a prime.

It is a super-2 number, since 2×101661531² = 20670133770527922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (101662531) 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, 16943586 + ... + 16943591.

It is an arithmetic number, because the mean of its divisors is an integer number (33887178).

Almost surely, 2^101661531 is an apocalyptic number.

101661531 is a deficient number, since it is larger than the sum of its proper divisors (33887181).

101661531 is an equidigital number, since it uses as much as digits as its factorization.

101661531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33887180.

The product of its (nonzero) digits is 540, while the sum is 24.

The square root of 101661531 is about 10082.7343017656. The cubic root of 101661531 is about 466.7154901866.

The spelling of 101661531 in words is "one hundred one million, six hundred sixty-one thousand, five hundred thirty-one".