1257740542 has 8 divisors (see below), whose sum is σ = 1886895216. Its totient is φ = 628775472.

The previous prime is 1257740521. The next prime is 1257740543. The reversal of 1257740542 is 2450477521.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×1257740542² = 3163822541980907528, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1257740543) 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, 29458 + ... + 58165.

It is an arithmetic number, because the mean of its divisors is an integer number (235861902).

Almost surely, 2^1257740542 is an apocalyptic number.

1257740542 is a deficient number, since it is larger than the sum of its proper divisors (629154674).

1257740542 is an equidigital number, since it uses as much as digits as its factorization.

1257740542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94802.

The product of its (nonzero) digits is 78400, while the sum is 37.

The square root of 1257740542 is about 35464.6379087677. The cubic root of 1257740542 is about 1079.4363033426.

The spelling of 1257740542 in words is "one billion, two hundred fifty-seven million, seven hundred forty thousand, five hundred forty-two".