90542539621 has 2 divisors, whose sum is σ = 90542539622. Its totient is φ = 90542539620.

The previous prime is 90542539489. The next prime is 90542539667. The reversal of 90542539621 is 12693524509.

It is an a-pointer prime, because the next prime (90542539667) can be obtained adding 90542539621 to its sum of digits (46).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53645508225 + 36897031396 = 231615^2 + 192086^2 .

It is an emirp because it is prime and its reverse (12693524509) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90542539621 - 2¹⁵ = 90542506853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90542539691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45271269810 + 45271269811.

It is an arithmetic number, because the mean of its divisors is an integer number (45271269811).

Almost surely, 2^90542539621 is an apocalyptic number.

It is an amenable number.

90542539621 is a deficient number, since it is larger than the sum of its proper divisors (1).

90542539621 is an equidigital number, since it uses as much as digits as its factorization.

90542539621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 583200, while the sum is 46.

The spelling of 90542539621 in words is "ninety billion, five hundred forty-two million, five hundred thirty-nine thousand, six hundred twenty-one".