78811801 has 2 divisors, whose sum is σ = 78811802. Its totient is φ = 78811800.

The previous prime is 78811793. The next prime is 78811807. The reversal of 78811801 is 10811887.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43099225 + 35712576 = 6565^2 + 5976^2 .

It is a cyclic number.

It is not a de Polignac number, because 78811801 - 2³ = 78811793 is a prime.

It is a super-2 number, since 2×78811801² = 12422599953727202, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78811807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39405900 + 39405901.

It is an arithmetic number, because the mean of its divisors is an integer number (39405901).

Almost surely, 2^78811801 is an apocalyptic number.

It is an amenable number.

78811801 is a deficient number, since it is larger than the sum of its proper divisors (1).

78811801 is an equidigital number, since it uses as much as digits as its factorization.

78811801 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3584, while the sum is 34.

The square root of 78811801 is about 8877.6010836261. The cubic root of 78811801 is about 428.7430410235.

The spelling of 78811801 in words is "seventy-eight million, eight hundred eleven thousand, eight hundred one".