1213157749 has 8 divisors (see below), whose sum is σ = 1245823488. Its totient is φ = 1180777680.

The previous prime is 1213157741. The next prime is 1213157767. The reversal of 1213157749 is 9477513121.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1213157749 - 2³ = 1213157741 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213157741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62797 + ... + 79810.

It is an arithmetic number, because the mean of its divisors is an integer number (155727936).

Almost surely, 2^1213157749 is an apocalyptic number.

It is an amenable number.

1213157749 is a deficient number, since it is larger than the sum of its proper divisors (32665739).

1213157749 is a wasteful number, since it uses less digits than its factorization.

1213157749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142835.

The product of its digits is 52920, while the sum is 40.

The square root of 1213157749 is about 34830.4141376470. The cubic root of 1213157749 is about 1066.5284024671.

The spelling of 1213157749 in words is "one billion, two hundred thirteen million, one hundred fifty-seven thousand, seven hundred forty-nine".