1978458311 has 2 divisors, whose sum is σ = 1978458312. Its totient is φ = 1978458310.

The previous prime is 1978458281. The next prime is 1978458319. The reversal of 1978458311 is 1138548791.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1978458311 - 2¹⁰ = 1978457287 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1978458319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 989229155 + 989229156.

It is an arithmetic number, because the mean of its divisors is an integer number (989229156).

Almost surely, 2^1978458311 is an apocalyptic number.

1978458311 is a deficient number, since it is larger than the sum of its proper divisors (1).

1978458311 is an equidigital number, since it uses as much as digits as its factorization.

1978458311 is an evil number, because the sum of its binary digits is even.

The product of its digits is 241920, while the sum is 47.

The square root of 1978458311 is about 44479.8641072564. The cubic root of 1978458311 is about 1255.3812402394.

The spelling of 1978458311 in words is "one billion, nine hundred seventy-eight million, four hundred fifty-eight thousand, three hundred eleven".