1221015319 has 2 divisors, whose sum is σ = 1221015320. Its totient is φ = 1221015318.

The previous prime is 1221015311. The next prime is 1221015347. The reversal of 1221015319 is 9135101221.

It is a weak prime.

It is an emirp because it is prime and its reverse (9135101221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221015319 - 2³ = 1221015311 is a prime.

It is a super-2 number, since 2×1221015319² = 2981756818465343522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221015293 and 1221015302.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221015311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610507659 + 610507660.

It is an arithmetic number, because the mean of its divisors is an integer number (610507660).

Almost surely, 2^1221015319 is an apocalyptic number.

1221015319 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221015319 is an equidigital number, since it uses as much as digits as its factorization.

1221015319 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 540, while the sum is 25.

The square root of 1221015319 is about 34943.0296196538. The cubic root of 1221015319 is about 1068.8260683224.

The spelling of 1221015319 in words is "one billion, two hundred twenty-one million, fifteen thousand, three hundred nineteen".