245139457 has 4 divisors (see below), whose sum is σ = 245198916. Its totient is φ = 245080000.

The previous prime is 245139403. The next prime is 245139481. The reversal of 245139457 is 754931542.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 754931542 = 2 ⋅377465771.

It can be written as a sum of positive squares in 2 ways, for example, as 69205761 + 175933696 = 8319^2 + 13264^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-245139457 is a prime.

It is a super-4 number, since 4×245139457⁴ (a number of 35 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (245139487) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23044 + ... + 31957.

It is an arithmetic number, because the mean of its divisors is an integer number (61299729).

Almost surely, 2^245139457 is an apocalyptic number.

It is an amenable number.

245139457 is a deficient number, since it is larger than the sum of its proper divisors (59459).

245139457 is an equidigital number, since it uses as much as digits as its factorization.

245139457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59458.

The product of its digits is 151200, while the sum is 40.

The square root of 245139457 is about 15656.9299992048. The cubic root of 245139457 is about 625.8511769104.

The spelling of 245139457 in words is "two hundred forty-five million, one hundred thirty-nine thousand, four hundred fifty-seven".