91219970 has 16 divisors (see below), whose sum is σ = 164541888. Its totient is φ = 36411120.

The previous prime is 91219951. The next prime is 91219979. The reversal of 91219970 is 7991219.

It is not an unprimeable number, because it can be changed into a prime (91219979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4496 + ... + 14235.

It is an arithmetic number, because the mean of its divisors is an integer number (10283868).

Almost surely, 2^91219970 is an apocalyptic number.

91219970 is a deficient number, since it is larger than the sum of its proper divisors (73321918).

91219970 is a wasteful number, since it uses less digits than its factorization.

91219970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19225.

The product of its (nonzero) digits is 10206, while the sum is 38.

The square root of 91219970 is about 9550.9146158889. The cubic root of 91219970 is about 450.1562749410.

It can be divided in two parts, 9121 and 9970, that added together give a palindrome (19091).

The spelling of 91219970 in words is "ninety-one million, two hundred nineteen thousand, nine hundred seventy".