122780137 has 4 divisors (see below), whose sum is σ = 130002516. Its totient is φ = 115557760.

The previous prime is 122780131. The next prime is 122780149. The reversal of 122780137 is 731087221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 35712576 + 87067561 = 5976^2 + 9331^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-122780137 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 122780099 and 122780108.

It is not an unprimeable number, because it can be changed into a prime (122780131) 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, 3611164 + ... + 3611197.

It is an arithmetic number, because the mean of its divisors is an integer number (32500629).

Almost surely, 2^122780137 is an apocalyptic number.

122780137 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

122780137 is a deficient number, since it is larger than the sum of its proper divisors (7222379).

122780137 is an equidigital number, since it uses as much as digits as its factorization.

122780137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7222378.

The product of its (nonzero) digits is 4704, while the sum is 31.

The square root of 122780137 is about 11080.6198833820. The cubic root of 122780137 is about 497.0224866922.

The spelling of 122780137 in words is "one hundred twenty-two million, seven hundred eighty thousand, one hundred thirty-seven".