101256989 has 4 divisors (see below), whose sum is σ = 102203424. Its totient is φ = 100310556.

The previous prime is 101256983. The next prime is 101256997. The reversal of 101256989 is 989652101.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-101256989 is a prime.

It is a super-2 number, since 2×101256989² = 20505955642692242, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101256983) 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, 473057 + ... + 473270.

It is an arithmetic number, because the mean of its divisors is an integer number (25550856).

Almost surely, 2^101256989 is an apocalyptic number.

It is an amenable number.

101256989 is a deficient number, since it is larger than the sum of its proper divisors (946435).

101256989 is an equidigital number, since it uses as much as digits as its factorization.

101256989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 946434.

The product of its (nonzero) digits is 38880, while the sum is 41.

The square root of 101256989 is about 10062.6531789583. The cubic root of 101256989 is about 466.0955998182.

The spelling of 101256989 in words is "one hundred one million, two hundred fifty-six thousand, nine hundred eighty-nine".