78231973 has 2 divisors, whose sum is σ = 78231974. Its totient is φ = 78231972.

The previous prime is 78231961. The next prime is 78231991. The reversal of 78231973 is 37913287.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64931364 + 13300609 = 8058^2 + 3647^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78231973 is a prime.

It is a super-2 number, since 2×78231973² = 12240483198945458, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78231913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39115986 + 39115987.

It is an arithmetic number, because the mean of its divisors is an integer number (39115987).

Almost surely, 2^78231973 is an apocalyptic number.

It is an amenable number.

78231973 is a deficient number, since it is larger than the sum of its proper divisors (1).

78231973 is an equidigital number, since it uses as much as digits as its factorization.

78231973 is an evil number, because the sum of its binary digits is even.

The product of its digits is 63504, while the sum is 40.

The square root of 78231973 is about 8844.8840015005. The cubic root of 78231973 is about 427.6890136898.

The spelling of 78231973 in words is "seventy-eight million, two hundred thirty-one thousand, nine hundred seventy-three".