742279921 has 2 divisors, whose sum is σ = 742279922. Its totient is φ = 742279920.

The previous prime is 742279831. The next prime is 742279927. The reversal of 742279921 is 129972247.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 487526400 + 254753521 = 22080^2 + 15961^2 .

It is a cyclic number.

It is not a de Polignac number, because 742279921 - 2²⁵ = 708725489 is a prime.

It is a super-2 number, since 2×742279921² = 1101958962239532482, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (742279927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 371139960 + 371139961.

It is an arithmetic number, because the mean of its divisors is an integer number (371139961).

Almost surely, 2^742279921 is an apocalyptic number.

It is an amenable number.

742279921 is a deficient number, since it is larger than the sum of its proper divisors (1).

742279921 is an equidigital number, since it uses as much as digits as its factorization.

742279921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 127008, while the sum is 43.

The square root of 742279921 is about 27244.8145708500. The cubic root of 742279921 is about 905.4321353307.

It can be divided in two parts, 74227 and 9921, that added together give a palindrome (84148).

The spelling of 742279921 in words is "seven hundred forty-two million, two hundred seventy-nine thousand, nine hundred twenty-one".