102042991 has 4 divisors (see below), whose sum is σ = 102078000. Its totient is φ = 102007984.

The previous prime is 102042989. The next prime is 102043001. The reversal of 102042991 is 199240201.

It is a happy number.

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 102042991 - 2¹ = 102042989 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 (102042491) 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, 12691 + ... + 19108.

It is an arithmetic number, because the mean of its divisors is an integer number (25519500).

Almost surely, 2^102042991 is an apocalyptic number.

102042991 is a deficient number, since it is larger than the sum of its proper divisors (35009).

102042991 is an equidigital number, since it uses as much as digits as its factorization.

102042991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35008.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 102042991 is about 10101.6330857936. The cubic root of 102042991 is about 467.2985067801.

The spelling of 102042991 in words is "one hundred two million, forty-two thousand, nine hundred ninety-one".