90781247 has 2 divisors, whose sum is σ = 90781248. Its totient is φ = 90781246.

The previous prime is 90781199. The next prime is 90781277. The reversal of 90781247 is 74218709.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 90781247 - 2¹⁶ = 90715711 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 90781247.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90781277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45390623 + 45390624.

It is an arithmetic number, because the mean of its divisors is an integer number (45390624).

Almost surely, 2^90781247 is an apocalyptic number.

90781247 is a deficient number, since it is larger than the sum of its proper divisors (1).

90781247 is an equidigital number, since it uses as much as digits as its factorization.

90781247 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28224, while the sum is 38.

The square root of 90781247 is about 9527.9193426477. The cubic root of 90781247 is about 449.4334384241.

The spelling of 90781247 in words is "ninety million, seven hundred eighty-one thousand, two hundred forty-seven".