78228621156551 has 2 divisors, whose sum is σ = 78228621156552. Its totient is φ = 78228621156550.

The previous prime is 78228621156503. The next prime is 78228621156563. The reversal of 78228621156551 is 15565112682287.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78228621156551 - 2¹⁰ = 78228621155527 is a prime.

It is a super-2 number, since 2×78228621156551² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78228621156151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39114310578275 + 39114310578276.

It is an arithmetic number, because the mean of its divisors is an integer number (39114310578276).

Almost surely, 2^{78228621156551} is an apocalyptic number.

78228621156551 is a deficient number, since it is larger than the sum of its proper divisors (1).

78228621156551 is an equidigital number, since it uses as much as digits as its factorization.

78228621156551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16128000, while the sum is 59.

The spelling of 78228621156551 in words is "seventy-eight trillion, two hundred twenty-eight billion, six hundred twenty-one million, one hundred fifty-six thousand, five hundred fifty-one".