61369991 has 2 divisors, whose sum is σ = 61369992. Its totient is φ = 61369990.

The previous prime is 61369969. The next prime is 61370009. The reversal of 61369991 is 19996316.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61369991 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61369291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30684995 + 30684996.

It is an arithmetic number, because the mean of its divisors is an integer number (30684996).

Almost surely, 2^61369991 is an apocalyptic number.

61369991 is a deficient number, since it is larger than the sum of its proper divisors (1).

61369991 is an equidigital number, since it uses as much as digits as its factorization.

61369991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 78732, while the sum is 44.

The square root of 61369991 is about 7833.9001142471. The cubic root of 61369991 is about 394.4439990267.

The spelling of 61369991 in words is "sixty-one million, three hundred sixty-nine thousand, nine hundred ninety-one".