97781797 has 4 divisors (see below), whose sum is σ = 97801600. Its totient is φ = 97761996.

The previous prime is 97781791. The next prime is 97781833. The reversal of 97781797 is 79718779.

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 97781797 - 2⁷ = 97781669 is a prime.

It is a super-2 number, since 2×97781797² = 19122559649098418, 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 (97781791) 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, 4204 + ... + 14602.

It is an arithmetic number, because the mean of its divisors is an integer number (24450400).

Almost surely, 2^97781797 is an apocalyptic number.

It is an amenable number.

97781797 is a deficient number, since it is larger than the sum of its proper divisors (19803).

97781797 is a wasteful number, since it uses less digits than its factorization.

97781797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19802.

The product of its digits is 1555848, while the sum is 55.

The square root of 97781797 is about 9888.4678793026. The cubic root of 97781797 is about 460.7011943067.

The spelling of 97781797 in words is "ninety-seven million, seven hundred eighty-one thousand, seven hundred ninety-seven".