97866781 has 4 divisors (see below), whose sum is σ = 99525600. Its totient is φ = 96207964.

The previous prime is 97866767. The next prime is 97866787. The reversal of 97866781 is 18766879.

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 not a de Polignac number, because 97866781 - 2⁵ = 97866749 is a prime.

It is a super-2 number, since 2×97866781² = 19155813646603922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (97866787) 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, 829321 + ... + 829438.

It is an arithmetic number, because the mean of its divisors is an integer number (24881400).

Almost surely, 2^97866781 is an apocalyptic number.

It is an amenable number.

97866781 is a deficient number, since it is larger than the sum of its proper divisors (1658819).

97866781 is a wasteful number, since it uses less digits than its factorization.

97866781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1658818.

The product of its digits is 1016064, while the sum is 52.

The square root of 97866781 is about 9892.7640727958. The cubic root of 97866781 is about 460.8346236849.

The spelling of 97866781 in words is "ninety-seven million, eight hundred sixty-six thousand, seven hundred eighty-one".