78377947 has 2 divisors, whose sum is σ = 78377948. Its totient is φ = 78377946.

The previous prime is 78377927. The next prime is 78377969. The reversal of 78377947 is 74977387.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78377947 is a prime.

It is a super-2 number, since 2×78377947² = 12286205151869618, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78377894 and 78377903.

It is not a weakly prime, because it can be changed into another prime (78377917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39188973 + 39188974.

It is an arithmetic number, because the mean of its divisors is an integer number (39188974).

Almost surely, 2^78377947 is an apocalyptic number.

78377947 is a deficient number, since it is larger than the sum of its proper divisors (1).

78377947 is an equidigital number, since it uses as much as digits as its factorization.

78377947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2074464, while the sum is 52.

The square root of 78377947 is about 8853.1320446495. The cubic root of 78377947 is about 427.9548584731.

The spelling of 78377947 in words is "seventy-eight million, three hundred seventy-seven thousand, nine hundred forty-seven".