1098981397 has 2 divisors, whose sum is σ = 1098981398. Its totient is φ = 1098981396.

The previous prime is 1098981353. The next prime is 1098981421. The reversal of 1098981397 is 7931898901.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1082015236 + 16966161 = 32894^2 + 4119^2 .

It is a cyclic number.

It is not a de Polignac number, because 1098981397 - 2²⁷ = 964763669 is a prime.

It is a super-2 number, since 2×1098981397² = 2415520221904143218, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1098981197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 549490698 + 549490699.

It is an arithmetic number, because the mean of its divisors is an integer number (549490699).

Almost surely, 2^1098981397 is an apocalyptic number.

It is an amenable number.

1098981397 is a deficient number, since it is larger than the sum of its proper divisors (1).

1098981397 is an equidigital number, since it uses as much as digits as its factorization.

1098981397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 979776, while the sum is 55.

The square root of 1098981397 is about 33150.8883289724. Note that the first 3 decimals coincide. The cubic root of 1098981397 is about 1031.9613856538.

The spelling of 1098981397 in words is "one billion, ninety-eight million, nine hundred eighty-one thousand, three hundred ninety-seven".