78377468121 has 6 divisors (see below), whose sum is σ = 113211898410. Its totient is φ = 52251645408.

The previous prime is 78377468087. The next prime is 78377468137. The reversal of 78377468121 is 12186477387.

It can be written as a sum of positive squares in only one way, i.e., 71577651600 + 6799816521 = 267540^2 + 82461^2 .

It is not a de Polignac number, because 78377468121 - 2²⁵ = 78343913689 is a prime.

It is a super-2 number, since 2×78377468121² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78377468021) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4354303776 + ... + 4354303793.

It is an arithmetic number, because the mean of its divisors is an integer number (18868649735).

Almost surely, 2^78377468121 is an apocalyptic number.

It is an amenable number.

78377468121 is a deficient number, since it is larger than the sum of its proper divisors (34834430289).

78377468121 is a wasteful number, since it uses less digits than its factorization.

78377468121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8708607575 (or 8708607572 counting only the distinct ones).

The product of its digits is 3161088, while the sum is 54.

The spelling of 78377468121 in words is "seventy-eight billion, three hundred seventy-seven million, four hundred sixty-eight thousand, one hundred twenty-one".